Archives of the Sphere Online Judgeclassical problemset

Editors:

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[Trichromatic] XilinX Gustav Sennov Ruslan Matula Fotile 3xian Adrian Kosowski Phan Cng Minh Saransh Bansal JaceTheMindSculptor ! include(L.ppt) Adrian KuegelHieu suhash Minh abdelkarim Ivan Katani Nguyen Varun Garg Kotb Mohammad Marco Jalan Abhilash I Rahul Gallotta Spooky Fidel Schaposnik sieunhan Nikhil Dobrzycki Pawe Garg Bin Jin Pomykalski Ahmed Aly numerixinstitutes kawmia Patryk Pablo Ariel Heiber Adam Dzedzej Noszly Csaba problem setters islam Paulo Costa d RobertNguyen abhijithGerbicz xiaodao reddy Chinh CamiloP Borisov Nikola Andrs Varela Ali Arous aekdycoin ??????? Len Gawrychowski Pawel Jain Kunal Lordxfastx priyamehtanit David Garca Soriano Francky KBR Kashyap Le n Czajka Tomek Khue Race Somani Ajay with time Micha Maafiejski Jonas Wagner ukasz Kuszner Thanh-Vy Hua Mostafa Saad John Rizzo Alfonso2 Peterssen Prof_Utonium_????? Wanderley Guimares OmarIM Joon Young Seo Buda ElAzazy Subrahmanyam dce coders Alvaro Javier Medina HWK Naumenko Andrey Velaga RomanMahmud Balboa Sol amit karmakar Iqram WahbA Raziman T V setters Devilproblem sevenkplus VOJ D Meja-Posada Andrs MichaAhmedTu AndresUTN FRSF NguyenCzuczman Coach Tellez Samir Dinh David Moran Arteaga JeroenRafael Frank Bransen Bidhan Roy Siddharth Kothari Jelani Nelson Matthew Reeder IvanDilts skd062 Ben Metelsky (Minilek) Rafal Swarnaprakash Kashyap Ng Minh u+c Pavel Kuznetsov Angel Paredes Krishnakumar Adrian Satja Kurdija HemantLeonardo Andrs Verma Qu Jun Neal Wu Azat Taryhchiyev Rojas DuarteRidowan Muhammad jack(chakradarraju) Olson Avellaneda Alex Anderson Fabio Ortiz Daniel Gmez Didier Tjandra Satria Anil Kishore Quan Hoang Hong Krzysztof Lewko Gunawan Rofael Dereniowski Darek Emil Prasanna MateusDantas Brian BiVan Quang Nguyen Gareev Glavina Stjepan Fonseca Fernando Huy Piotr owiec Palii Ikhaduri [ITA] Miorel-Lucian Diego Satoba Radhakrishnan Phenomenal HNUE Chen Xiaohong Luka Kalinovcic lost Bobby Xiao cegprakash Paranoid Android Troika::Bytes Paul Draper Venezuelan John Mario Paritosh Aggarwal ??? Programming League SimonGordon Mir Wasi Ahmed Mark Gog Robin Nittka Mahesh Chandra XeRoN!X Fendy Kosnatha Christian Kauth SharmaJain Nikunj Unknown

Manukranth kipoujr Hayk Saribekyan Pandian Oleg Chernyakhovskiy SantiagoPiwakowski Bng Konrad Zubieta Jargon Pande P.KasthuriSachdeva Himanshu RanganAditya UNI Training himanshu Kluczek Krzysztof jain :-P Efime LovroPiotrowski Piotr Marian Tomasz Goluch Gogu Puzar arun Andres Galvis Khan Shashank Azam Piotr Kkol Muntasir Kumar Jakub afin Jonathan Irvin Gunawan Abhishek Mishra Marek Kotewicz .:: Debanjan ::. Piyush Kumar Pripoae Toni [UFCG] Phyllipe Csar bristyDE & Friends Alex, Infinity Erik Lonarek Khnh Tamer KAREN Xun Nguye^~n Neal Zane Reinier Csar Mujica Hdez Jayendra Singh HAMBARDZUMYAN Nghia Nguyen Hoang SALVO Radu Grigore Yash Rahul bnta2 pankaj Hussain Kara Fallah BSRK Aditya Anil Shanbhag lxyxynt Rudradev Basak Manohar Singh vijay Horvat Goran Sebastian Kanthak Walrus Ankit KumarOsuch rizwan hudda Vats Bogusaw K. Ahmad Faiyaz mohammad mahmoodi Narek Saribekyan Mislav Balunovi avinash Merriman Stephen Avinash Devendra Agarwal B.R.ARVIND Ammar Qadri paradigm2k10 Amlesh Jayakumar Leandro Castillo Valdes Abhishek Tiwari Egor Rychcicki Robert Thomas Dybdahl Ahle DominikPatel Vishrut Gleich Le Trong Dao Zvonimir Medic Jared Deckard Bartomiej Kowalski rajeshsr Edwin Guzman Marcos Kawakami TonyArguello Luis Beta Lambda The quick brown fox jumps Daniel Ampuero Camilo Bravo Valds Min2 over the lazy dog Vincenzo Bonifaci Frane Kurtovi om Shafaet_csedu Diogo Soares [UFAM] jiazhipeng nhs Paulo Roberto Santos de Divyanshu Ranjan Mayank Tuteja Lukas Mai Sousa Kumar Anurag Ivan Alfonso Olamendy Josef Ziegler akaki le me :-((Dul Tadeusz :-(( Balajiganapathi S Vexorian Govind Lahoti [UFPR] Ricardo Oliveira Tii Tomasz Niedzwiecki Freak Admins Martin Bader kojak_ praveen123 Zhang Taizhi bashrc is back Jose Daniel Rodrguez .:: Pratik ::. Tom Chen Juan Sebastian Beltran Morales Rodolfo Miquilarena omar alkattan Rojas Balakrishnan Robin Lee Mauro Persano Hari BEAN MR. P != NP Slobodan Rodriguez Swapnil R.Mehta Abel Nieto David Gmez Gowri Sundaram !(accepted) karthikeyan gogo40 tille Mesbah Amr Shashank Tandon Lukmanul Hakim Maciej Ferizovic Romal Thoppilan Damir Boniecki Yandry Perez mukulrajput Lukasz Wrona tmb

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Last updated: 2013-01-09 09:01:47

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PrefaceThis electronic material contains a set of algorithmic problems, forming the archives of the Sphere Online Judge (http://www.spoj.com/), classical problemset. The document can be accessed at the following URLs: in PostScript format: http://www.spoj.com/problems/classical.ps in Portable Document Format: http://www.spoj.com/problems/classical.pdf These resources are constantly updated to synchronise with the ever-changing hypertext version of the problems, and to include newly added problems. If you have obtained this document from another source, it is strongly recommended that you should download the current version from one of the aforementioned URLs. Enjoy problem-solving at the Sphere Online Judge! Disclaimer from the Editors. Despite our best efforts, it is possible that this document contains errors or that some of the content differs slightly from its original hypertext form. We take no responsibility for any such faults and their consequences. We neither authorise nor approve use of this material for any purpose other than facilitating problem solving at the Sphere Online Judge site; nor do we guarantee its fitness for any purpose whatsoever. The layout of the problems in this document is the copyright of the Editors named on the cover (as determined by the appropriate footers in the problem description). The content is the copyright of the respective Editor unless the copyright holder is otherwise stated in the resource section. The document as a whole is not protected by copyright, and fragments of it are to be regarded independently. No responsibility is taken by the Editors if use or redistribution of this document violates either their or third party copyright laws. When referring to or citing the whole or a fragment of this document, please state clearly the aforementioned URLs at which the document is to be found, as well as the resources from which the problems you are referring to originally came. Remarks concerning this document should be sent to the following e-mail address: contact@spoj.com.

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Table of Contents1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. Problem TEST (1. Life, the Universe, and Everything) Problem PRIME1 (2. Prime Generator) Problem SBSTR1 (3. Substring Check (Bug Funny)) Problem ONP (4. Transform the Expression) Problem PALIN (5. The Next Palindrome) Problem ARITH (6. Simple Arithmetics) Problem BULK (7. The Bulk!) Problem CMPLS (8. Complete the Sequence!) Problem DIRVS (9. Direct Visibility) Problem CMEXPR (10. Complicated Expressions) Problem FCTRL (11. Factorial) Problem MMIND (12. The Game of Master-Mind) Problem HOTLINE (13. Hotline) Problem IKEYB (14. I-Keyboard) Problem SHPATH (15. The Shortest Path) Problem TETRA (16. Sphere in a tetrahedron) Problem CRYPTO1 (17. The Bytelandian Cryptographer (Act I)) Problem CRYPTO2 (18. The Bytelandian Cryptographer (Act II)) Problem CRYPTO3 (19. The Bytelandian Cryptographer (Act III)) Problem CRYPTO4 (20. The Bytelandian Cryptographer (Act IV)) Problem TRICENTR (22. Triangle From Centroid) Problem PIR (23. Pyramids) Problem FCTRL2 (24. Small factorials) Problem POUR1 (25. Pouring water) Problem BSHEEP (26. Build the Fence) Problem SBANK (27. Sorting Bank Accounts) Problem HMRO (28. Help the Military Recruitment Office!) Problem HASHIT (29. Hash it!) Problem BLINNET (30. Bytelandian Blingors Network) Problem MUL (31. Fast Multiplication) Problem NHAY (32. A Needle in the Haystack) Problem TRIP (33. Trip) Problem RUNAWAY (34. Run Away) Problem EQBOX (35. Equipment Box) Problem CODE1 (36. Secret Code) Problem PROPKEY (37. The Proper Key) Problem LABYR1 (38. Labyrinth) Problem PIGBANK (39. Piggy-Bank) Problem STONE (40. Lifting the Stone) Problem WORDS1 (41. Play on Words) Problem ADDREV (42. Adding Reversed Numbers) Problem BOOKS1 (43. Copying Books) Problem SCYPHER (44. Substitution Cipher) Problem COMMEDIA (45. Commedia dell Arte) Problem SCRAPER (47. Skyscraper Floors)

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46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92.

Problem BEADS (48. Glass Beads) Problem HAREFOX (49. Hares and Foxes) Problem INCARDS (50. Invitation Cards) Problem TOUR (51. Fake tournament) Problem JULKA (54. Julka) Problem JASIEK (55. Jasiek) Problem DYZIO (56. Dyzio) Problem SUPPER (57. Supernumbers in a permutation) Problem PICAD (58. Crime at Piccadily Circus) Problem BIA (59. Bytelandian Information Agency) Problem DANCE (60. The Gordian Dance) Problem BRCKTS (61. Brackets) Problem IMP (62. The Imp) Problem SQRBR (63. Square Brackets) Problem PERMUT1 (64. Permutations) Problem BALL1 (65. Ball) Problem CRSCNTRY (66. Cross-country) Problem CUTOUT (67. Cutting out) Problem EXPR1 (68. Expression) Problem MOULDS (69. Moulds) Problem RELATS1 (70. Relations) Problem TREE1 (71. Tree) Problem BAC (73. Bacterial) Problem DIVSUM (74. Divisor Summation) Problem EDIT1 (75. Editor) Problem EDIT2 (76. Editor Inverse) Problem BRICKS (77. New bricks disorder) Problem MARBLES (78. Marbles) Problem EASYPIE (82. Easy Problem) Problem BUNDLE (83. Bundling) Problem SHORTCUT (84. Shortcut) Problem DICE1 (85. Dice Contest) Problem RAIN1 (86. November Rain) Problem FOOTBALL (87. Football) Problem TREE2 (88. Which is Next) Problem HANGLET (89. Hang or not to hang) Problem MINIMAX (90. Minimizing maximizer) Problem TWOSQRS (91. Two squares or not two squares) Problem CUTSQRS (92. Cutting off Squares) Problem MAYA (94. Numeral System of the Maya) Problem STPAR (95. Street Parade) Problem SHOP (96. Shopping) Problem PARTY (97. Party Schedule) Problem DFLOOR (98. Dance Floor) Problem BUS (99. Bus) Problem BABTWR (100. Tower of Babylon) Problem FISHER (101. Fishmonger)

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93. Problem LITEPIPE (102. GX Light Pipeline Inc) 94. Problem HIGH (104. Highways) 95. Problem ALICEBOB (105. Alice and Bob) 96. Problem BINSTIRL (106. Binary Stirling Numbers) 97. Problem MAYACAL (107. Calendar of the Maya) 98. Problem MORSE (108. Decoding Morse Sequences) 99. Problem EXCHNG (109. Exchanges) 100. Problem CISTFILL (110. Fill the Cisterns) 101. Problem SEGVIS (112. Horizontally Visible Segments) 102. Problem FAMILY (115. Family) 103. Problem INTERVAL (116. Intervals) 104. Problem RHOMBS (118. Rhombs) 105. Problem SERVERS (119. Servers) 106. Problem SOLIT (120. Solitaire) 107. Problem TTABLE (121. Timetable) 108. Problem STEVE (122. Voracious Steve) 109. Problem PAYING (123. Paying in Byteland) 110. Problem RENT (130. Rent your airplane and make money) 111. Problem SQDANCE (131. Square dance) 112. Problem HELPR2D2 (132. Help R2-D2!) 113. Problem PHONY (134. Phony Primes) 114. Problem MAWORK (135. Men at work) 115. Problem TRANS (136. Transformation) 116. Problem PARTIT (137. Partition) 117. Problem POSTERS (138. Election Posters) 118. Problem MAZE (139. The Long and Narrow Maze) 119. Problem LONER (140. The Loner) 120. Problem GLUE (142. Johnny and the Glue) 121. Problem ALIENS (145. Aliens) 122. Problem MULTIPLY (146. Fast Multiplication Again) 123. Problem TAUT (147. Tautology) 124. Problem MLAND (148. Land for Motorways) 125. Problem FSHEEP (149. Fencing in the Sheep) 126. Problem PLONK (150. Where to Drink the Plonk?) 127. Problem COURIER (151. The Courier) 128. Problem SCALES (153. Balancing the Stone) 129. Problem ROCK (154. Sweet and Sour Rock) 130. Problem PALSEC (160. Choosing a Palindromic Sequence) 131. Problem PAINTTMP (174. Paint templates) 132. Problem POLY1 (175. Polygon) 133. Problem SUM1SEQ (176. Sum of one-sequence) 134. Problem ABWORDS (177. AB-words) 135. Problem ROADNET (178. Road net) 136. Problem WORDEQ (179. Word equations) 137. Problem CONTPACK (180. How to pack containers) 138. Problem SCUBADIV (181. Scuba diver) 139. Problem WINDOW1 (182. Window)

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140. 141. 142. 143. 144. 145. 146. 147. 148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164. 165. 166. 167. 168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184. 185. 186.

Problem ASCIRC (183. Assembler circuits) Problem ATMS (184. Automatic Teller Machines) Problem CHASE1 (185. Chase) Problem LITELANG (186. The lightest language) Problem FLBRKLIN (187. Flat broken lines) Problem RECTNG1 (188. Rectangles) Problem MUSKET (196. Musketeers) Problem EMPTY (199. Empty Cuboids) Problem MONODIG (200. Monodigital Representations) Problem POLYGAME (201. The Game of Polygons) Problem ROCKETS (202. Rockets) Problem POTHOLE (203. Potholers) Problem SLEEP (204. Sleepwalker) Problem ICERINK (205. Icerink) Problem BITMAP (206. Bitmap) Problem THREECOL (207. Three-coloring of binary trees) Problem STORE (208. Store-keeper) Problem MAP (209. The Map) Problem ALTARS (210. The Altars) Problem PRIMIT (211. Primitivus recurencis) Problem WATER (212. Water among Cubes) Problem PANIC (215. Panic in the Plazas) Problem SOPARADE (217. Soldiers on Parade) Problem PHRASES (220. Relevant Phrases of Annihilation) Problem VONNY (224. Vonny and her dominos) Problem JEWELS (226. Jewelry and Fashion) Problem ORDERS (227. Ordering the Soldiers) Problem SHAMAN (228. Shamans) Problem SORTING (229. Sorting is easy) Problem ZEBRA (231. The Zebra Crossing) Problem HOLIDAY1 (234. Getting Rid of the Holidays (Act I)) Problem VFMUL (235. Very Fast Multiplication) Problem ROMAN (236. Converting number formats) Problem SUMITR (237. Sums in a Triangle) Problem HOLIDAY2 (238. Getting Rid of the Holidays (Act II)) Problem BTOUR (239. Tour de Byteland) Problem BLOCKS (241. Arranging the Blocks) Problem STABLEMP (243. Stable Marriage Problem) Problem SQRROOT (245. Square Root) Problem CHOCOLA (247. Chocolate) Problem CTAIN (260. Containers) Problem TRIPART (261. Triangle Partitioning) Problem CONNECT (262. Connections) Problem PERIOD (263. Period) Problem CORNET (264. Corporative Network) Problem CAVE (272. Cave Exploration) Problem WMELON (274. Johnny and the Watermelon Plantation)

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187. 188. 189. 190. 191. 192. 193. 194. 195. 196. 197. 198. 199. 200. 201. 202. 203. 204. 205. 206. 207. 208. 209. 210. 211. 212. 213. 214. 215. 216. 217. 218. 219. 220. 221. 222. 223. 224. 225. 226. 227. 228. 229. 230. 231. 232. 233.

Problem WATERWAY (275. The Water Ringroad) Problem CTGAME (277. City Game) Problem BICYCLE (278. Bicycle) Problem INUMBER (279. Interesting number) Problem LIFTS (280. Lifts) Problem MUDDY (282. Muddy Fields) Problem NAPTIME (283. Naptime) Problem SCITIES (286. Selfish Cities) Problem NETADMIN (287. Smart Network Administrator) Problem PON (288. Prime or Not) Problem POLYEQ (290. Polynomial Equations) Problem CUBERT (291. Cube Root) Problem ALIBB (292. Alibaba) Problem OFBEAT (293. Officers on the Beat) Problem TWORK (296. Teamwork is Crucial) Problem AGGRCOW (297. Aggressive cows) Problem CABLETV (300. Cable TV Network) Problem BOOK (301. Booklets) Problem CANTON (302. Count on Cantor) Problem UCUBE (303. The Unstable Cube) Problem RATTERN (309. The Room Pattern) Problem PITPAIR (318. Pythagorean Legacy) Problem WINDMILL (325. The Tall Windmills) Problem PLATON (327. Platon and Socrates) Problem BISHOPS (328. Bishops) Problem CALLS (329. Calls) Problem HARDQ (332. Hard Question) Problem PHDISP (334. The Philosophical Dispute) Problem EOPERA (336. Exchange Operations) Problem SEQ (339. Recursive Sequence) Problem POKER (344. Poker) Problem MIXTURES (345. Mixtures) Problem COINS (346. Bytelandian gold coins) Problem EXPEDI (348. Expedition) Problem AROUND (349. Around the world) Problem LANDSCAP (350. Landscaping) Problem HAN01 (351. Ha-noi!) Problem ACT (359. Alpha Centauri Tennis) Problem IGARB (362. Ignore the Garbage) Problem LISA (364. Pocket Money) Problem PHIDIAS (365. Phidias) Problem FARMER (366. Farmer) Problem EMPODIA (367. Empodia) Problem CSTREET (368. Cobbled streets) Problem MATH1 (369. Math I) Problem ONEZERO (370. Ones and zeros) Problem BENEFACT (372. The Benefactor)

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234. 235. 236. 237. 238. 239. 240. 241. 242. 243. 244. 245. 246. 247. 248. 249. 250. 251. 252. 253. 254. 255. 256. 257. 258. 259. 260. 261. 262. 263. 264. 265. 266. 267. 268. 269. 270. 271. 272. 273. 274. 275. 276. 277. 278. 279. 280.

Problem GREED (373. Greedy island) Problem MATRIX (374. Count maximum matrices) Problem QTREE (375. Query on a tree) Problem ACS (376. A concrete simulation) Problem TAXI (377. Taxi) Problem PERMUT2 (379. Ambiguous Permutations) Problem BINGO (380. Bullshit Bingo) Problem CHICAGO (381. 106 miles to Chicago) Problem DECORATE (382. Decorate the wall) Problem EUROPEAN (383. European railroad tracks) Problem FOOL (384. Any fool can do it) Problem GAME (385. Game schedule required) Problem HELP (386. Help the problem setter) Problem TOURS (387. Travelling tours) Problem MENU (388. Menu) Problem HOSPITAL (389. Use of Hospital Facilities) Problem BILLIARD (390. Billiard) Problem RAILROAD (391. Railroads) Problem SPIN (392. Spin) Problem HEXAGON (393. Hexagon) Problem ACODE (394. Alphacode) Problem APRIME (395. Anti-prime Sequences) Problem HITOMISS (396. Hit or Miss) Problem CONDUIT (397. I Conduit) Problem RPGAMES (398. Roll Playing Games) Problem TRANK (399. Team Rankings) Problem TOANDFRO (400. To and Fro) Problem TRANSL (401. Translations) Problem HIKE (402. Hike on a Graph) Problem FRACTION (403. Sort fractions) Problem SCANNER (404. Scanner) Problem TCUTTER (405. Tin Cutter) Problem LOGIC (406. Logic) Problem RNUMBER (407. Random Number) Problem JRIDE (408. Jill Rides Again) Problem DELCOMM (409. DEL Command) Problem VHUFFM (410. Variable Radix Huffman Encoding) Problem NUMQDW (411. Number of quite different words) Problem COVER (412. K-path cover) Problem WPUZZLES (413. Word Puzzles) Problem BONFIRE (414. Equatorial Bonfire) Problem DIV15 (416. Divisibility by 15) Problem LAZYPROG (417. The lazy programmer) Problem NECKLACE (418. Necklace) Problem TRANSP (419. Transposing is Fun) Problem AROAD (421. Another Road Problem) Problem TRANSP2 (422. Transposing is Even More Fun)

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281. 282. 283. 284. 285. 286. 287. 288. 289. 290. 291. 292. 293. 294. 295. 296. 297. 298. 299. 300. 301. 302. 303. 304. 305. 306. 307. 308. 309. 310. 311. 312. 313. 314. 315. 316. 317. 318. 319. 320. 321. 322. 323. 324. 325. 326. 327.

Problem ASSIGN (423. Assignments) Problem HAJIME (425. Kill evil instantly) Problem PARTPALI (428. Particular Palindromes) Problem TCNUMFL (449. Simple Numbers with Fractions Conversion) Problem TFOSS (484. Fossil in the Ice) Problem CLTZ (515. Collatz) Problem ZZPERM (518. Zig-Zag Permutation) Problem DIV (526. Divisors) Problem DIV2 (530. Divisors 2) Problem INCR (598. Increasing Subsequences) Problem QUEST4 (660. Dungeon of Death) Problem QUEST5 (661. Nail Them) Problem SUBS (665. String it out) Problem VOCV (666. Con-Junctions) Problem LSORT (676. Sorting is not easy) Problem BROW (677. A place for the brewery) Problem HANOI07 (681. Building the Tower) Problem PAIRINT (682. Pairs of Integers) Problem ASSIGN4 (684. Another Assignment Problem) Problem SEQPAR (685. Partition the sequence) Problem REPEATS (687. Repeats) Problem SAM (688. Toy Cars) Problem LWAR (693. Lethal Warfare) Problem DISUBSTR (694. Distinct Substrings) Problem UFAST (695. Unite Fast) Problem LIAR (696. Liar Liar) Problem MWORDS (697. Matrix Words) Problem PLHOP (698. Plane Hopping) Problem HKNAP (699. Huge Knap Sack) Problem BPRED (700. Branch Prediction) Problem EXPAND (702. Barn Expansion) Problem SERVICE (703. Mobile Service) Problem PSTRING (704. Remove The String) Problem SUBST1 (705. New Distinct Substrings) Problem TFSETS (707. Triple-Free Sets) Problem NICEDAY (709. The day of the competitors) Problem PRO (726. Promotion) Problem MAXIMUS (729. Move your armies) Problem IVAN (734. Ivan and his interesting game) Problem MDST (735. Minimum Diameter Spanning Tree) Problem TREE (738. Another Counting Problem) Problem NEG2 (739. The Moronic Cowmpouter) Problem TRT (740. Treats for the Cows) Problem STEAD (741. Steady Cow Assignment) Problem LPERMUT (744. Longest Permutation) Problem TEM (757. Thermal Luminescence) Problem CH3D (760. Convex Hull 3D)

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328. 329. 330. 331. 332. 333. 334. 335. 336. 337. 338. 339. 340. 341. 342. 343. 344. 345. 346. 347. 348. 349. 350. 351. 352. 353. 354. 355. 356. 357. 358. 359. 360. 361. 362. 363. 364. 365. 366. 367. 368. 369. 370. 371. 372. 373. 374.

Problem ARCHPLG (780. The Archipelago) Problem TRIOPT (827. Trigonometric optimization) Problem OPTM (839. Optimal Marks) Problem WM06 (850. Soccer Choreography) Problem SWAPS (861. Counting inversions) Problem DNA (866. DNA Translation) Problem CUBES (867. Perfect Cubes) Problem IMPORT (869. Galactic Import) Problem BASE (870. Basically Speaking) Problem SEQUENCE (871. Letter Sequence Analysis) Problem MARKUP (872. Mark-up) Problem TRANSMIT (898. Transmitters) Problem WSCIPHER (899. Ws Cipher) Problem SPLIT (900. Split Windows) Problem INDEXGEN (901. Index Generation) Problem HANGOVER (902. Hangover) Problem DOUBLEVI (903. Double Vision) Problem IMAGE (904. Image Perimeters) Problem MATRIX2 (912. Submatrix of submatrix) Problem QTREE2 (913. Query on a tree II) Problem FTOUR (944. Free Tour) Problem IM (962. Intergalactic Map) Problem EN (964. Entrapment) Problem PB (967. Parking Bay) Problem BIRTHDAY (972. Birthday) Problem MOBILE (987. Mobile) Problem CFRAC (996. Continuous Fractions) Problem MATRIOSH (999. Generalized Matrioshkas) Problem EQDIV (1000. Equidivisions) Problem BROUL (1001. Babylonian Roulette) Problem UJ (1002. Uncle Jack) Problem QUILT (1003. Little Quilt) Problem POLYCODE (1004. Polygon Encoder) Problem AIBOHP (1021. Aibohphobia) Problem ANGELS (1022. Angels and Devils) Problem COMCB (1024. Complete Chess Boards) Problem FASHION (1025. Fashion Shows) Problem FAVDICE (1026. Favorite Dice) Problem FPOLICE (1027. Fool the Police) Problem HUBULLU (1028. Hubulullu) Problem MATSUM (1029. Matrix Summation) Problem EIGHTS (1030. Triple Fat Ladies) Problem UPSUB (1031. Up Subsequence) Problem GSS1 (1043. Can you answer these queries I) Problem CTRICK (1108. Card Trick) Problem SUDOKU (1110. Sudoku) Problem NSTEPS (1112. Number Steps)

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375. 376. 377. 378. 379. 380. 381. 382. 383. 384. 385. 386. 387. 388. 389. 390. 391. 392. 393. 394. 395. 396. 397. 398. 399. 400. 401. 402. 403. 404. 405. 406. 407. 408. 409. 410. 411. 412. 413. 414. 415. 416. 417. 418. 419. 420. 421.

Problem TOE1 (1161. Tic-Tac-Toe ( I )) Problem TOE2 (1162. Tic-Tac-Toe ( II )) Problem JAVAC (1163. Java vs C ++) Problem DEADFR (1166. Dead Fraction) Problem MINCOUNT (1167. Move To Invert) Problem SORTBIT (1182. Sorted bit squence) Problem PALACE (1183. Accomodate the palace) Problem ORIGLIFE (1267. Origin of Life) Problem CNEASY (1268. CN Tower (Easy)) Problem CNHARD (1269. CN Tower (Hard)) Problem PNTBYNUM (1270. Paint By Numbers) Problem CFRAC2 (1285. Continuous Fractions Again) Problem SUMFOUR (1296. 4 values whose sum is 0) Problem PARTSUM (1325. Partial Sums) Problem CHASE (1326. A Chase In WonderLand) Problem KPMATRIX (1329. Matrix) Problem KPMAZE (1335. Maze) Problem CZ_PROB1 (1391. Summing to a Square Prime) Problem CATM (1418. The Cats and the Mouse) Problem NGM (1419. A Game with Numbers) Problem GEOM (1420. Geometry and a Square) Problem FIRM (1421. Goods) Problem KPPOLY (1431. Projections Of A Polygon) Problem KPSUM (1433. The Sum) Problem KPEQU (1434. Equation) Problem PT07X (1435. Vertex Cover) Problem PT07Y (1436. Is it a tree) Problem PT07Z (1437. Longest path in a tree) Problem ARCTAN (1440. Use of Function Arctan) Problem CLEVER (1441. The Clever Typist) Problem CHAIN (1442. Strange Food Chain) Problem DELCOMM2 (1444. DEL Command II) Problem BRCKGAME (1447. A Game of Toy Bricks) Problem COVER2 (1448. 3D Cover) Problem SEQ1 (1451. 01 Sequence) Problem CAKE (1452. Birthday Cake) Problem OPTSUB (1453. Optimal Connected Subset) Problem MEMDIS (1454. Memory Distribution) Problem ANALYSER (1455. Program Analyser) Problem BLUEEQ (1457. Help Blue Mary Please! (Act I)) Problem BLUEEQ2 (1458. Help Blue Mary Please! (Act II)) Problem AEROLITE (1459. The Secret of an Aerolite) Problem GALAXY (1460. A Simple Calculator in the Galaxy) Problem DRAGON (1461. Greedy Hydra) Problem BARB (1462. Barbarians) Problem ROBOT (1463. Robot Number M) Problem EDIT3 (1464. Editor II)

13

422. 423. 424. 425. 426. 427. 428. 429. 430. 431. 432. 433. 434. 435. 436. 437. 438. 439. 440. 441. 442. 443. 444. 445. 446. 447. 448. 449. 450. 451. 452. 453. 454. 455. 456. 457. 458. 459. 460. 461. 462. 463. 464. 465. 466. 467. 468.

Problem CHRIS (1465. On the Way to Find Chris) Problem CASHIER (1466. Blue Mary Needs Help Again) Problem RAIN2 (1468. Outside it is now raining) Problem SEQ2 (1470. Another Sequence Problem) Problem PRLGAME (1471. A Game of Pearls) Problem TOMJERRY (1472. Tom and Jerry) Problem LEMON (1473. Lemon Tree in the Moonlight) Problem WORMS (1475. VII - Act IV) Problem PROFIT (1476. Maximum Profit) Problem PT07A (1477. Play with a Tree) Problem PT07B (1478. The Easiest Problem) Problem PT07C (1479. The GbAaY Kingdom) Problem PT07D (1480. Let us count 1 2 3) Problem PT07F (1482. A short vacation in Disneyland) Problem PT07G (1483. Colorful Lights Party) Problem PT07H (1484. Search in XML) Problem PT07J (1487. Query on a tree III) Problem MOLE (1505. Whac-a-Mole) Problem RSORTING (1526. Ranklist Sorting) Problem BLUEEQ3 (1536. Help Blue Mary Please! (Act III)) Problem MKJUMPS (1538. Making Jumps) Problem MOBILE2 (1552. Mobiles) Problem BACKUP (1553. Backup Files) Problem ZOO (1554. Zoo) Problem GSS2 (1557. Can you answer these queries II) Problem TREEOI14 (1644. Trees) Problem AMATH (1671. Another Mathematical Problem) Problem GIWED (1672. The Great Indian Wedding) Problem AMBM (1673. Ambitious Manager) Problem EXPLOSN (1674. The Explosion) Problem FUSION (1675. Fusion Cube) Problem GEN (1676. Text Generator) Problem HALLOW (1677. Halloween treats) Problem TREASURY (1678. Royal Treasury) Problem CYLINDER (1681. Cylinder) Problem EXPRESS (1683. Expressions) Problem FREQUENT (1684. Frequent values) Problem GROCERY (1685. Grocery store) Problem LOGIC2 (1687. Logic II) Problem EASYPROB (1688. A Very Easy Problem!) Problem HARDP (1689. Hard Problem) Problem COCONUTS (1693. Coconuts) Problem GRC (1695. Grandpas Rubik Cube) Problem WIJGT (1696. Will Indiana Jones Get There) Problem OFORTUNE (1697. Ohgas Fortune) Problem PLSEARCH (1698. Polygonal Line Search) Problem NSYSTEM (1699. Numeral System)

14

469. 470. 471. 472. 473. 474. 475. 476. 477. 478. 479. 480. 481. 482. 483. 484. 485. 486. 487. 488. 489. 490. 491. 492. 493. 494. 495. 496. 497. 498. 499. 500. 501. 502. 503. 504. 505. 506. 507. 508. 509. 510. 511. 512. 513. 514. 515.

Problem TRSTAGE (1700. Traveling by Stagecoach) Problem EOWAMRT (1701. Earth Observation with a Mobile Robot Team) Problem CLEANRBT (1702. Cleaning Robot) Problem ACMAKER (1703. ACM (ACronymMaker)) Problem CDOWN (1704. Countdown) Problem GAMEFIL (1705. The Game of Efil) Problem QKP (1706. Queens, Knights and Pawns) Problem RELINETS (1707. Reliable Nets) Problem SQCOUNT (1708. Square Count) Problem SWTHIN (1709. Swamp Things) Problem TWENDS (1710. Two Ends) Problem PRMLX (1712. Permalex) Problem SCALE (1713. Funny scales) Problem NCKLCE (1715. Another Necklace Problem) Problem GSS3 (1716. Can you answer these queries III) Problem RP (1722. Life, the Universe, and Everything II) Problem BMJ (1723. Bee Maja) Problem TRICOUNT (1724. Counting Triangles) Problem IMPORT1 (1725. The Importance) Problem EXCHANGE (1726. Exchange) Problem CPRMT (1728. Common Permutation) Problem TCOUNT2 (1730. Counting Triangles II) Problem TCOUNT3 (1731. Counting Triangles III) Problem EQU2 (1739. Yet Another Equation) Problem TETRIS3D (1741. Tetris 3D) Problem POLEVAL (1744. Evaluate the polynomial) Problem SEQPAR2 (1748. Sequence Partitioning II) Problem DIVSUM2 (1754. Divisor Summation (Hard)) Problem NQUEEN (1771. Yet Another N-Queen Problem) Problem DETER2 (1772. Find The Determinant II) Problem ALL (1774. All Discs Considered) Problem BOOLE (1775. Boolean Logic) Problem DNALAB (1776. DNA Laboratory) Problem ICAMPSEQ (1784. IOICamp Sequence) Problem CODE (1785. Code) Problem DANGER (1786. In Danger) Problem ENCONDIN (1787. Run Length Encoding) Problem FRACTAN (1788. Fractan) Problem GREEDULM (1789. Huffmans Greed) Problem HEAPULM (1790. Binary Search Heap Construction) Problem GEN2 (1793. Text Generater II) Problem DRAGON2 (1794. Greedy Hydra II) Problem CARD (1797. Cardsharper) Problem ASSIST (1798. Assistance Required) Problem BOTTOM (1799. The Bottom of a Graph) Problem CONTEST (1800. Fixed Partition Contest Management) Problem DRINK (1801. Drink, on Ice)

15

516. 517. 518. 519. 520. 521. 522. 523. 524. 525. 526. 527. 528. 529. 530. 531. 532. 533. 534. 535. 536. 537. 538. 539. 540. 541. 542. 543. 544. 545. 546. 547. 548. 549. 550. 551. 552. 553. 554. 555. 556. 557. 558. 559. 560. 561. 562.

Problem EDGE (1802. Edge) Problem FOLD (1803. Fold) Problem GENETIC (1804. Genetic Code) Problem HISTOGRA (1805. Largest Rectangle in a Histogram) Problem ORZ (1810. Nuclear Plants) Problem LCS (1811. Longest Common Substring) Problem LCS2 (1812. Longest Common Substring II ) Problem WA (1815. Problems Collection (Volume X)) Problem FTOUR2 (1825. Free tour II) Problem SUDOKU2 (1833. Sudoku) Problem SETSTACK (1835. The SetStack Computer) Problem PIE (1837. Pie) Problem TICKET (1838. Ticket to Ride) Problem BOOKCASE (1839. The Bookcase) Problem PQUEUE (1840. Printer Queue) Problem PPATH (1841. Prime Path) Problem LINELAND (1842. Lineland Airport) Problem LEONARDO (1843. Leonardo Notebook) Problem MICEMAZE (1845. Mice and Maze) Problem PFDEP (1846. Project File Dependencies) Problem NOCHANGE (1847. No Change) Problem MKWAVES (1865. Making Waves) Problem MKPALS (1866. Making Pals) Problem MKMONEY (1868. Making Money) Problem MKMOOM (1869. Making Mountains Out Of Molehills) Problem MKLABELS (1870. Making Labels) Problem MKBUDGET (1871. Making A Budget) Problem ACARGO (1873. Accumulate Cargo) Problem BWHEELER (1874. Burrows Wheeler Precompression) Problem COOLNUMS (1875. Cool Numbers) Problem DRAGONCU (1876. Dragon Curves) Problem EPURSE (1877. Enrich my purse) Problem FCATTLE (1878. Farmers Cattle) Problem GAMETIME (1879. Game Time) Problem HANOICAL (1880. Hanoi Calls) Problem ICODER (1881. Instruction Decoder) Problem RECTANGL (1960. Rectangles) Problem ROMANRDS (1961. Roman Roads) Problem CIRCLES (1962. Circles) Problem IMGPROJ (1963. Image Projections) Problem MMCUT (1964. Tree cut) Problem SETCOV (1965. Set Cover) Problem SKIVALL (1966. Ski Valley) Problem ACFRAC (1991. Another Continuous Fractions Problem) Problem BOX (2000. Boxes (Hard)) Problem RNG (2002. Random Number Generator) Problem MINUS (2005. Minus Operation)

16

563. 564. 565. 566. 567. 568. 569. 570. 571. 572. 573. 574. 575. 576. 577. 578. 579. 580. 581. 582. 583. 584. 585. 586. 587. 588. 589. 590. 591. 592. 593. 594. 595. 596. 597. 598. 599. 600. 601. 602. 603. 604. 605. 606. 607. 608. 609.

Problem BALIFE (2006. Load Balancing) Problem COUNT (2007. Another Very Easy Problem! WOW!!!) Problem BACKPACK (2008. Dab of Backpack) Problem CRYPTO (2009. Cryptography) Problem ROLLBALL (2019. The Rolling Ball) Problem PEBBMOV (2021. Moving Pebbles) Problem TRUTHORL (2022. Truth Or Lie) Problem ONEINSTR (2023. One Instruction Computer Simulator) Problem YKH (2031. Please help You-Know-Who) Problem TILING (2038. Rectangle Tiling) Problem REMGAME (2047. Stone Removing Game) Problem CERC07B (2050. Strange Billboard) Problem CERC07C (2051. Cell Phone) Problem CERC07H (2052. Hexagonal Parcels) Problem CERC07K (2053. Key Task) Problem CERC07L (2054. Gates of Logic) Problem CERC07N (2055. Weird Numbers) Problem CERC07P (2056. Rectangular Polygon) Problem CERC07R (2058. Reaux! Sham! Beaux!) Problem CERC07S (2059. Robotic Sort) Problem CERC07W (2060. Tough Water Level) Problem MINDIST (2070. Minimum Distance) Problem CANDY (2123. Candy I) Problem FCTRL4 (2124. Last Non-Zero Digit of Factorials) Problem LABYR2 (2125. Number Labyrinth) Problem RAIN3 (2127. Rain) Problem KROW (2128. K-In-A-Row) Problem CAKE2 (2129. Cake) Problem TROLLS (2130. Trolls) Problem GETBACK (2131. Get Back!) Problem PUZZLE2 (2132. Puzzle) Problem CANDY2 (2136. Candy II) Problem PIB (2138. Pibonacci) Problem GOSSIPER (2139. Gossipers) Problem FAIRONOT (2140. (un)Fair Play) Problem GARDEN (2141. Golden Garden) Problem FLOWERS (2142. Arranging Flowers) Problem DEPEND (2143. Dependency Problems) Problem FOREST (2144. K Edge-disjoint Branchings) Problem ROOT (2147. Root of a Linear Equation) Problem CANDY3 (2148. Candy III) Problem BAISED (2149. Biased Standings) Problem SUBSEQ (2150. Counting Subsequences) Problem CALCULAT (2151. Digital Calculator) Problem FRACTAL (2152. Hilbert Curve) Problem IMATCH (2153. Internet is Faulty) Problem KRUSKAL (2154. Kruskal)

17

610. 611. 612. 613. 614. 615. 616. 617. 618. 619. 620. 621. 622. 623. 624. 625. 626. 627. 628. 629. 630. 631. 632. 633. 634. 635. 636. 637. 638. 639. 640. 641. 642. 643. 644. 645. 646. 647. 648. 649. 650. 651. 652. 653. 654. 655. 656.

Problem ABSYS (2157. Anti-Blot System) Problem CAKE3 (2159. Delicious Cake) Problem HERE (2160. Here-There) Problem JPIX (2161. Pixel Shuffle) Problem TOWER (2162. Towers of Powers) Problem AMCODES (2171. Ambiguous Codes) Problem EMOTICON (2175. Emoticons) Problem MUSIC (2185. Musical Optimization) Problem MKPAIRS (2189. Making Pairs) Problem TAN1 (2202. Tan and His Interesting Game) Problem BALLOON (2270. Balloons in a Box) Problem UCODES (2271. Undecodable Codes) Problem DESERT (2272. Crossing the Desert) Problem FERRY (2273. Ferries) Problem ISLHOP (2274. Island Hopping) Problem OIL (2275. Toil for Oil) Problem RECTNG2 (2276. Partitions) Problem SSORT (2277. Silly Sort) Problem LEXBRAC (2317. Bracket Sequence) Problem WORDS (2318. Overlapping Words) Problem BIGSEQ (2319. Sequence) Problem DISTANCE (2320. Manhattan) Problem SEGMENTS (2321. Segments) Problem TREEGAME (2322. Tree Game) Problem COMPASS (2323. Broken Compass) Problem MARIOGAM (2324. Mario) Problem STRDIST (2325. String Distance) Problem LIS2 (2371. Another Longest Increasing Subsequence Problem) Problem ARRANGE (2412. Arranging Amplifiers) Problem BUILD (2413. Building Beacons) Problem CCOST (2414. Calculate The Cost) Problem RESIST (2415. Kirchhof Law) Problem DSUBSEQ (2416. Distinct Subsequences) Problem ENEMY (2417. Eliminate The Enemies) Problem FFROG (2418. Flying Frogs) Problem GLGRID (2419. G-Line Grid) Problem HHAND (2420. Hospital at Hands) Problem ININT (2421. Incrementing The Integer) Problem JAZZYJOB (2422. Jazzy Job) Problem MINTRIAN (2423. Minimal Triangulations of Graphs) Problem PLD (2426. Palindromes) Problem RABBIT1 (2450. Counting Rabbits) Problem PHONELIN (2485. Phone Lines) Problem MAGIC4 (2511. Magic Program IV) Problem GNY07C (2525. Encoding) Problem GNY07D (2526. Decoding) Problem GNY07E (2527. Flipping Burned Pancakes)

18

657. 658. 659. 660. 661. 662. 663. 664. 665. 666. 667. 668. 669. 670. 671. 672. 673. 674. 675. 676. 677. 678. 679. 680. 681. 682. 683. 684. 685. 686. 687. 688. 689. 690. 691. 692. 693. 694. 695. 696. 697. 698. 699. 700. 701. 702. 703.

Problem GNY07F (2528. Monkey Vines) Problem GNY07G (2529. Model Rocket Height) Problem GNY07H (2530. Tiling a Grid With Dominoes) Problem GNY07I (2531. Spatial Concepts Test) Problem PERMUT3 (2565. Another Permutation Problem) Problem CLK (2631. Chomp) Problem SC1 (2643. Starcraft I) Problem KPARCH (2648. Archiver) Problem KPSORT (2649. Weird sorting) Problem WAR (2658. Art of War) Problem EXAMPLE (2660. Example) Problem ILLUM (2661. Illumination) Problem PUTIN (2662. Put a Point in a Hyperspace) Problem QTREE4 (2666. Query on a tree IV) Problem POLYSSQ (2668. Polygon) Problem MSTS (2670. Count Minimum Spanning Trees) Problem SPP (2699. Recursive Sequence (Version II)) Problem UNTITLED (2709. Untitled Problem) Problem GSS4 (2713. Can you answer these queries IV) Problem COWCAR (2714. Cow Cars) Problem GLASNICI (2715. Glasnici) Problem QUADAREA (2716. Maximal Quadrilateral Area) Problem ARMY (2727. Army Strength) Problem BREAK (2728. Breaking in) Problem INVENT (2731. Inventing Test Data) Problem KEQ (2733. K Equal Digits) Problem LARGE (2734. Large party) Problem RAIL (2735. Simplify the Railroad System) Problem PRHYME (2737. Perfect Rhyme) Problem SUMSUMS (2742. Summing Sums) Problem PRETILE (2743. Prefix Tiling) Problem INCSEQ (2815. Increasing Subsequences) Problem CSUBSEQS (2816. Common Subsequences) Problem INCDSEQ (2817. Distinct Increasing Subsequences) Problem RRSCHED (2826. Round-Robin Scheduling) Problem TLE (2829. Time Limit Exceeded) Problem DETER3 (2832. Find The Determinant III) Problem SDGAME (2833. Super Dice Game) Problem MLE (2835. Memory Limit Exceeded) Problem BROKEN (2852. Broken Keyboard) Problem PDECODE (2853. Decode the Strings) Problem FOREST2 (2855. Forest) Problem HELPBOB (2856. Help Bob) Problem SDGAME2 (2877. Another understanding of Super Dice Game) Problem KNIGHTS (2878. Knights of the Round Table) Problem DOCTOR (2879. The Cow Doctor) Problem WILD (2880. Wild West)

19

704. 705. 706. 707. 708. 709. 710. 711. 712. 713. 714. 715. 716. 717. 718. 719. 720. 721. 722. 723. 724. 725. 726. 727. 728. 729. 730. 731. 732. 733. 734. 735. 736. 737. 738. 739. 740. 741. 742. 743. 744. 745. 746. 747. 748. 749. 750.

Problem CLONE (2881. Find the Clones) Problem WARE (2882. The Warehouse) Problem WIDGET (2883. Widget Factory) Problem MARTIAN (2884. Martian Mining) Problem WORDRING (2885. Word Rings) Problem PARTY2 (2898. Party of Cloaked Killers) Problem VOL (2899. Volunteers) Problem GEOPROB (2901. One Geometry Problem) Problem CANDY4 (2902. Candy IV) Problem TRANSP1 (2903. Transportation) Problem NOTATRI (2905. Not a Triangle) Problem GCD2 (2906. GCD2) Problem GSS5 (2916. Can you answer these queries V) Problem QTREE5 (2939. Query on a tree V) Problem UNTITLE1 (2940. Untitled Problem II) Problem SHOOTING (2944. Emmons) Problem ECLIPSE (2946. Eclipse) Problem PAINTBLK (2962. Painting Blocks (Act I)) Problem PAINTBLC (2963. Painting Blocks (Act II)) Problem ELECTRO (3002. Electrophoretic) Problem FILTER (3003. Median Filter) Problem LIFEGAME (3004. Life Game) Problem LAND (3005. Subdividing a Land) Problem LINE (3006. Connect Line Segments) Problem OILCOMP (3007. Oil Company) Problem RPS (3008. Finding the Top RPS Player) Problem VORONOI (3009. Revenge of Voronoi) Problem WALL (3010. Castle Wall) Problem SOLDIER (3033. Help the soldier) Problem SEQ5 (3070. How many subsequences) Problem MOD (3105. Power Modulo Inverted) Problem DICTSUB (3106. Dictionary Subsequences) Problem ODDDIV (3107. Odd Numbers of Divisors) Problem GRAPHGAM (3108. Charlesbert and Merangelou) Problem STRLCP (3109. Longest Common Prefix) Problem PALNUM (3110. Palindromic Number) Problem STABARDS (3111. Stabards) Problem STSTRING (3112. Strings) Problem GORELIAN (3133. Here We Go(relians) Again) Problem PERMSG (3166. Permutation Exponentiation) Problem LINES (3184. Game of Lines) Problem DOORSPEN (3195. Doors and Penguins) Problem PALIM (3208. Yet Another Longest Palindrome Problem) Problem TYPESET (3249. Typesettin) Problem SLINK (3251. Slink) Problem EDS (3253. Electronic Document Security) Problem GUARD (3254. Guard)

20

751. 752. 753. 754. 755. 756. 757. 758. 759. 760. 761. 762. 763. 764. 765. 766. 767. 768. 769. 770. 771. 772. 773. 774. 775. 776. 777. 778. 779. 780. 781. 782. 783. 784. 785. 786. 787. 788. 789. 790. 791. 792. 793. 794. 795. 796. 797.

Problem RACETIME (3261. Race Against Time) Problem SA04C (3305. Roman Patrollers) Problem SA04D (3306. Very Special Boxes ) Problem HEXTILE (3307. Hex Tile Equations) Problem BRIDGES2 (3308. The Bridges of San Mochti) Problem BULLETIN (3309. Bulletin Board) Problem SERIALN (3310. Serial Numbers) Problem UMNOZAK (3314. Umnozak) Problem DOUBLE (3322. Doubled Numbers) Problem HIGHWAY (3347. Cestarine) Problem STACK (3359. Stack) Problem IMGREC2 (3360. Digital Image Recognition) Problem SVADA (3363. Svada) Problem ROUNDT (3372. Round Table) Problem PERMCODE (3373. Permutation Code) Problem SCAVHUNT (3374. Scavenger Hunt) Problem STAMPS (3375. Stamps) Problem PARKINGL (3376. Parking Lot) Problem BUGLIFE (3377. A Bugs Life) Problem SSHUFFLE (3379. String Shuffle) Problem TOURIST (3380. Tourist) Problem HIGHWAYS (3381. Highways) Problem MONSTER (3382. Monster Trap) Problem YODA (3385. Yoda Goes Palindromic !) Problem CHMAZE (3387. Changing Maze) Problem DNPALIN (3388. Double Near Palindromes) Problem KNIGHTSR (3389. The Knights of the Round Circle) Problem TRIBE2 (3390. Tribe Council) Problem NOTOKNOT (3393. Knot or Not) Problem LAGRANGE (3394. Lagranges Four-Square Theorem) Problem SAMER08A (3405. Almost Shortest Path) Problem SAMER08B (3406. Bases) Problem SAMER08C (3407. Candy) Problem SAMER08D (3408. DNA Sequences) Problem SAMER08E (3409. Electricity) Problem SAMER08F (3410. Feynman) Problem SAMER08G (3411. Pole Position) Problem SAMER08H (3412. Higgs Boson) Problem SAMER08I (3413. Traveling Shoemaker Problem) Problem SAMER08J (3414. Bora Bora) Problem SAMER08K (3415. Shrinking Polygons) Problem FALLINGI (3420. Falling Ice) Problem OROSNAKE (3426. Ouroboros Snake) Problem HIST2 (3436. Histogram) Problem LASTDIG (3442. The last digit) Problem CEPC08B (3459. SkyScrapers) Problem SONG (3461. Song Contest)

21

798. 799. 800. 801. 802. 803. 804. 805. 806. 807. 808. 809. 810. 811. 812. 813. 814. 815. 816. 817. 818. 819. 820. 821. 822. 823. 824. 825. 826. 827. 828. 829. 830. 831. 832. 833. 834. 835. 836. 837. 838. 839. 840. 841. 842. 843. 844.

Problem RAMP (3462. The Skateparks New Ramps) Problem ROBIN (3463. Robintron) Problem DRIVE (3465. Drive through MegaCity) Problem DEPOSIT (3476. Deposit) Problem BABY (3477. Baby) Problem BEGIN (3483. Begin) Problem CROSSBIT (3484. Crossbits) Problem ELIM (3486. Elimination) Problem TOPCODE (3488. The Top-Code) Problem HIDTRI (3490. Hidden Triangle) Problem BRAILLE (3492. Braille Transcription) Problem NBLTHIEF (3495. The Nobel Thief) Problem MATRICA (3543. Matrica) Problem BST (3544. Binary Search Tree) Problem NAJKRACI (3545. Najkraci) Problem BOYSCOUT (3576. Boy Scouts) Problem PARITY (3577. Parity) Problem HASH (3578. Hashing) Problem DISJPATH (3579. Disjoint Paths) Problem TREESIM (3581. Tree Similarity) Problem RSTAURNT (3582. Restaurant Tab) Problem PATHEADS (3591. Patting Heads) Problem CATTLEB (3678. Cattle Bruisers) Problem MOOPIZZA (3679. Moo University - Emergency Pizza Order) Problem KGSS (3693. Maximum Sum) Problem PROOT (3713. Primitive Root) Problem SNOOKER (3723. Snooker) Problem RAINBOW (3724. Rainbow Ride) Problem TREX (3725. Taming a T-REX) Problem SUBSUMS (3749. Subset Sums) Problem GEORGE (3763. George) Problem STREET (3791. Street) Problem LUBEN (3831. Lubenica) Problem KRUS (3832. Kruska) Problem TRES (3833. Tresnja) Problem VCIRCLES (3863. Area of circles) Problem RELJEF (3865. Reljef) Problem VPALIN (3866. Finding Palindromes) Problem VBOSS (3867. Who is The Boss) Problem VMILI (3870. Military Story) Problem GCDEX (3871. GCD Extreme) Problem VPARTY (3872. Party At School) Problem WHEN (3884. When (You Believe)) Problem BOBALLS (3894. Bouncing Balls) Problem BYTESE1 (3920. Lucius Dungeon) Problem BYTESE2 (3921. The Great Ball) Problem BYTESM1 (3922. Mystical River)

22

845. 846. 847. 848. 849. 850. 851. 852. 853. 854. 855. 856. 857. 858. 859. 860. 861. 862. 863. 864. 865. 866. 867. 868. 869. 870. 871. 872. 873. 874. 875. 876. 877. 878. 879. 880. 881. 882. 883. 884. 885. 886. 887. 888. 889. 890. 891.

Problem BYTESM2 (3923. Philosophers Stone) Problem BYTESH1 (3924. Filchs Dilemna) Problem FROGGER (3999. FROGGER) Problem GALLUP (4000. GALLUP) Problem SUBWAYPL (4003. Subway planning) Problem CPU (4004. Exploding CPU) Problem PHONELST (4033. Phone List) Problem CUCKOO (4036. Cuckoo Hashing) Problem KPGAME (4060. A game with probability) Problem MORPH (4069. Morphing is Fun) Problem TWOPROF (4070. Two Professors) Problem EPALIN (4103. Extend to Palindrome) Problem FASTFLOW (4110. Fast Maximum Flow) Problem ELLIPSE (4142. Ellipse) Problem DOMINO2 (4157. Domino) Problem HS08PAUL (4164. A conjecture of Paul Erds) Problem HS08FOUR (4166. Four colors) Problem SQFREE (4168. Square-free integers) Problem DROOT (4172. Multiplicative digital root) Problem KPURSUIT (4176. A Knightly Pursuit) Problem HERDING (4177. Herding) Problem LATTICE (4178. Distance on a square lattice) Problem TEMPTISL (4179. Temptation Island) Problem FCANDY (4182. Candy (Again)) Problem CCCCUBE (4185. Cube) Problem HS08CODE (4186. Break a New RSA system) Problem HS08EQ (4188. Amazing equality) Problem LANDING (4189. Landing) Problem DOMINOES (4197. Dominoes) Problem LEGO (4198. Lego) Problem HAMSTER1 (4200. Hamster flight) Problem RATING (4201. Coder Ratings) Problem BRPAR (4202. Brackets Parade) Problem MATCHING (4206. Fast Maximum Matching) Problem QUEEN (4235. Wandering Queen) Problem TTTABLE (4273. Train TimeTable) Problem BFROTATE (4275. rotate it) Problem AE3A (4305. Drilling) Problem EVERLAST (4324. The fate of the pineapple) Problem EBOXES (4343. Empty Boxes) Problem MATRIX1 (4357. Enter the Matrix) Problem DAGCNT (4407. Counting Arborescence) Problem FENCE1 (4408. Build a Fence) Problem AREA1 (4409. Circle vs Triangle) Problem REPAIR1 (4410. Repair the Door) Problem EXPR3 (4411. Counting Expressions) Problem FACTOR1 (4412. Factorization, Factorization, Factorization)

23

892. 893. 894. 895. 896. 897. 898. 899. 900. 901. 902. 903. 904. 905. 906. 907. 908. 909. 910. 911. 912. 913. 914. 915. 916. 917. 918. 919. 920. 921. 922. 923. 924. 925. 926. 927. 928. 929. 930. 931. 932. 933. 934. 935. 936. 937. 938.

Problem GEM (4413. Gem) Problem HIGHWAY1 (4414. Highway) Problem INTEGER1 (4415. Power of Integer) Problem JUMP1 (4416. Jumping Hands) Problem KPGRAPHS (4420. Counting Graphs) Problem GF2 (4421. Irreducible polynomials over GF2) Problem MIB (4429. Spelling Lists) Problem ARITH2 (4452. Simple Arithmetics II) Problem BOBALLS2 (4453. Bouncing Balls II) Problem BRCKTS2 (4454. Brackets II) Problem MOVIE (4455. Going to the Movies) Problem AIRLINES (4456. Jumbo Airlines) Problem SHOP2 (4457. Shopping II) Problem AIRLINE2 (4461. A Famous Airport Manager) Problem ANTTT (4465. The Ant) Problem PLAYFAIR (4476. Playfair Cracker) Problem EXPR4 (4478. Counting Expressions II) Problem GSS6 (4487. Can you answer these queries VI) Problem PGCD (4491. Primes in GCD Table) Problem UCI2009B (4523. Binomial Coefficients) Problem UCI2009D (4525. Digger Octaves) Problem FROGS (4528. Frog Wrestling) Problem BANDMATR (4533. Determinant of Banded Matrices) Problem ANARC08A (4546. Tobo or not Tobo) Problem ANARC08B (4549. Adding Sevens) Problem ANARC08C (4551. Match Maker) Problem ANARC08D (4552. Adding up Triangles) Problem ANARC08F (4555. Einbahnstrasse) Problem ANARC08G (4556. Think I will Buy Me a Football Team) Problem ANARC08H (4557. Musical Chairs) Problem ANARC08I (4558. I Speak Whales) Problem ANARC08J (4559. A Day at the Races) Problem CYCLERUN (4574. Riding in cycles) Problem ABCDEF (4580. ABCDEF) Problem GCJ08C (4585. Star Wars) Problem WLOO0707 (4586. Texas Trip) Problem FENCE3 (4587. Electric Fences) Problem NWERC04H (4588. SETI) Problem PMATRIX (4644. Proving Equivalences) Problem CCROSS (4656. Cross Mountain Climb) Problem GASWARS (4657. Gas Wars) Problem HHEMANT (4658. Help Hemant Verma) Problem WIRELESS (4666. Wireless) Problem GREMLINS (4667. Gremlins) Problem CCROSSX (4669. Cross Mountain Climb Extreme) Problem FUNPROB (4672. Yanu in Movie theatre) Problem TWICE (4681. Twice)

24

939. 940. 941. 942. 943. 944. 945. 946. 947. 948. 949. 950. 951. 952. 953. 954. 955. 956. 957. 958. 959. 960. 961. 962. 963. 964. 965. 966. 967. 968. 969. 970. 971. 972. 973. 974. 975. 976. 977. 978. 979. 980. 981. 982. 983. 984. 985.

Problem GPINTRI (4717. Grid Points in a Triangle) Problem HS09EQ (4784. Diophantine equation) Problem HS09SHIP (4785. Starship) Problem ZSEQ (4828. ZSequence) Problem BRI (4871. Bridge) Problem AMBIG (4881. Words on graphs) Problem DAGCNT2 (4882. Counting in a DAG) Problem RLM (4908. Run-Length Mathematics) Problem FACT1 (4941. Integer Factorization (20 digits)) Problem FACT0 (4942. Integer Factorization (15 digits)) Problem FACT2 (4948. Integer Factorization (29 digits)) Problem BRII (4951. Bridges! More bridges!) Problem GOALFR (4987. Goal for Ral) Problem MOWS (4988. Madrids One Way Streets) Problem FAKETSP (4993. Traveling Salesman) Problem LIM (5010. Lost in Madrid) Problem LFM (5011. Library for Madrid) Problem CRAZYR (5014. Crazy Receptionist) Problem CASTANET (5015. Decode the Castanets) Problem GUERNICA (5016. Guernica) Problem STRGAMB (5018. Street Gambler) Problem GCD3 (5084. Discrete Math Problem) Problem MBALL (5091. Feline Olympics - Mouseball) Problem PRETTY (5093. Pretty function) Problem MYSTIC (5102. Mystic Craft) Problem TOP10 (5103. Top 10) Problem SPAMD (5104. Spam Detection) Problem TUTMRBL (5107. Playing with Marbles) Problem SPHIWAY (5115. Two "Ways") Problem GERGOVIA (5117. Wine trading in Gergovia) Problem MINSEQ (5120. Minimal Possible String) Problem BOMB (5128. Bomb the Bridge) Problem PAIRGRPH (5142. A Pair of Graphs) Problem BNYINT (5143. Binary Integer) Problem CRYPTO6 (5144. Cryptography Reloaded (Act I)) Problem DEJAVU (5145. Dja vu) Problem CABLEXPR (5146. Experiment on a ... Cable) Problem FCSYS (5147. Fire-Control System) Problem STCKHOLM (5148. Get-Together at Stockholm) Problem HISTORY (5149. History of Languages) Problem JMFILTER (5150. Junk-Mail Filter) Problem ALICECUB (5151. Alices Cube) Problem BFALG (5152. Brute-force Algorithm EXTREME) Problem COMPRESS (5153. Compressed String) Problem CRYPTO7 (5154. Cryptography Reloaded (Act II)) Problem TETRIS2D (5155. Exciting Time) Problem FLOWERS2 (5156. Flowers Placement)

25

986. Problem TRACTOR (5157. Game Simulator) 987. Problem HEROARR (5158. Heroes Arrangement) 988. Problem IEXPOLRE (5159. Island Explorer) 989. Problem O2JAM (5160. Jinyuetuan Puzzle) 990. Problem FACVSPOW (5161. Factorial vs Power) 991. Problem VIENTIAN (5163. Tower of Vientiane) 992. Problem PAIRSORT (5182. Double Sorting) 993. Problem MONONUM (5196. Monotonous numbers) 994. Problem DIFFDIAG (5197. Differential Diagnosis) 995. Problem GARDENAR (5240. Area of a Garden) 996. Problem REC (5294. Recurrence) 997. Problem GNYR09F (5295. Adjacent Bit Counts) 998. Problem COMBAT (5296. Air Combat) 999. Problem INTERVA2 (5298. Interval Challenge) 1000. Problem MEXICAN (5300. Mexican Standoff) 1001. Problem QUERYSTR (5301. Query Problem) 1002. Problem TETRAVEX (5317. Tetravex Puzzle) 1003. Problem MINES4 (5373. Four Mines) 1004. Problem FISHNET (5446. Fishing Net) 1005. Problem ANARC09A (5449. Seinfeld) 1006. Problem ANARC09B (5450. Tiles of Tetris, Not!) 1007. Problem ANARC09C (5451. Not So Flat After All) 1008. Problem ANARC09D (5452. Hop Do not Walk) 1009. Problem ANARC09F (5453. Air Strike) 1010. Problem BIRD (5463. Bird or not bird) 1011. Problem CT (5464. Counting triangles) 1012. Problem DP (5465. Deliver pizza) 1013. Problem EQ (5466. Electronic queue) 1014. Problem FP (5467. Finding password) 1015. Problem GS (5468. Going to school) 1016. Problem HOUSES2 (5469. Houses) 1017. Problem HSEQ (5511. Heavy Sequences) 1018. Problem PHU09H (5522. Buy Your House) 1019. Problem PHU09K (5523. Highway Patrol) 1020. Problem BSMATH1 (5530. Math with Bases (Easy)) 1021. Problem KUTH (5531. Kutevi Hard) 1022. Problem SEQUOIA (5541. Sequoiadendron) 1023. Problem CPAIR (5542. Counting pairs) 1024. Problem BSMATH2 (5566. Math with Bases) 1025. Problem KMOVES (5609. Knight Moves) 1026. Problem ISUN1 (5637. LL and ErBao) 1027. Problem SERVICEH (5638. Mobile Service Hard) 1028. Problem NG0FRCTN (5640. Fractions on Tree) 1029. Problem DTPOLY (5649. Divide Polygon) 1030. Problem PATULJCI (5652. Snow White and the N dwarfs) 1031. Problem NG1FRCTN (5673. Fractions on Tree ( reloaded !)) 1032. Problem RESN04 (5676. STONE GAME )

26

1033. 1034. 1035. 1036. 1037. 1038. 1039. 1040. 1041. 1042. 1043. 1044. 1045. 1046. 1047. 1048. 1049. 1050. 1051. 1052. 1053. 1054. 1055. 1056. 1057. 1058. 1059. 1060. 1061. 1062. 1063. 1064. 1065. 1066. 1067. 1068. 1069. 1070. 1071. 1072. 1073. 1074. 1075. 1076. 1077. 1078. 1079.

Problem LASTDIG2 (5699. The last digit re-visited) Problem LPRIME (5703. Primes of Lambda) Problem KSEQ (5725. 123 Sequence) Problem PARADOX (5732. Paradox) Problem ALTPERM (5830. Alternating Permutations) Problem PERMJUMP (5831. Permutation Jumping) Problem ANDROUND (5832. AND Rounds) Problem XORROUND (5833. XOR Rounds) Problem TROOPS (5885. Troops of Sand Monsters) Problem CEOI09TR (5902. Tri) Problem SQFFACT (5911. Square-free Integers Factorization) Problem LENGFACT (5917. Factorial length) Problem FINDMAX (5969. Finding Maximum) Problem FINDPRM (5970. Finding Primes) Problem LCMSUM (5971. LCM Sum) Problem MAXSUMSQ (5972. Maximum Sum Sequences) Problem SELTEAM (5973. Selecting Teams) Problem TRKNIGHT (5975. Travelling Knight) Problem TRGRID (5976. Traversing Grid) Problem WEIRDFN (5977. Weird Function) Problem FRQPRIME (5978. Frequent Prime Ranges) Problem YAPP (5979. Yet Another Permutations Problem) Problem MATGAME (5980. Matrix Game) Problem DINGRP (6035. Dinner) Problem QCJ1 (6041. Mountain Walking) Problem QCJ2 (6042. Another Box Problem) Problem QCJ3 (6043. The Game) Problem QCJ4 (6044. Minimum Diameter Circle) Problem PBCGAME (6052. PBCGAME) Problem GCDSQF (6059. Another GCD problem) Problem SOCOLA (6072. Chocolate) Problem BRIDGE (6168. Building Bridges) Problem SSEQ (6169. Standing Sequence) Problem HOMEC (6170. Homecoming) Problem MAJOR (6171. Majority) Problem OAE (6172. OAE) Problem JANE (6187. Jane and Tarzan) Problem EDIST (6219. Edit distance) Problem INCPOWK (6221. Increasing Powers of K) Problem FERT21_0 (6236. Matches) Problem INVCNT (6256. Inversion Count) Problem FNRANK (6264. Rank of a Fraction) Problem NGM2 (6285. Another Game With Numbers) Problem SUMMUL (6286. Sum of products) Problem PYRA (6288. Treeramids) Problem BOMBER (6289. Bomberman) Problem ROBBERY2 (6290. Robbery 2)

27

1080. 1081. 1082. 1083. 1084. 1085. 1086. 1087. 1088. 1089. 1090. 1091. 1092. 1093. 1094. 1095. 1096. 1097. 1098. 1099. 1100. 1101. 1102. 1103. 1104. 1105. 1106. 1107. 1108. 1109. 1110. 1111. 1112. 1113. 1114. 1115. 1116. 1117. 1118. 1119. 1120. 1121. 1122. 1123. 1124. 1125. 1126.

Problem SHMOOGLE (6292. Shmoogle Wave) Problem YODANESS (6294. Yodaness Level) Problem EXPER (6296. Experiment) Problem ROOTCIPH (6297. Decipher) Problem MOVMRBL (6299. Move Marbles) Problem ARDA1 (6322. The hunt for Gollum) Problem NGON (6325. Many polygons) Problem ZUMA (6340. ZUMA) Problem RPSSL (6356. Rock-Paper-Scissors-Lizard-Spock) Problem SAMTWARR (6377. Two Array Problem) Problem KKKCT2 (6408. Counting Triangles 2) Problem MB1 (6450. PP numbers) Problem TDKPRIME (6470. Finding the Kth Prime) Problem TDPRIMES (6471. Printing some primes) Problem BOWLING1 (6477. Bowling) Problem HAMSTER2 (6478. Hamster Flight 2) Problem VGCD (6479. The Very Greatest Common Divisor) Problem PRIMES2 (6488. Printing some primes (Hard)) Problem KPRIMES2 (6489. Finding the Kth Prime (Hard)) Problem BCHOCO (6499. Breaking Chocolates) Problem DCOUNT (6500. Counting Diameter) Problem TSPAGAIN (6503. Travelling Salesman Again !) Problem JOCHEF (6517. Farmer Sepp) Problem NDIVPHI (6556. N DIV PHI_N) Problem NDIVPHI2 (6560. N DIV PHI_N (Hard)) Problem PRUBALL (6562. Esferas) Problem DIVCON (6576. Divide and conquer) Problem SEGTREE (6578. Segment Tree) Problem HCHAINS (6622. Islands and Hotel Chains) Problem SNOWGAME (6624. Snowball Game) Problem SEQ6 (6650. Consecutive sequence) Problem ELCS (6665. Easy Longest Common Substring) Problem GCJ101C (6678. Load Testing ) Problem BOCOMP (6690. A - Comparison Expressions) Problem GCJ101BB (6691. Picking Up Chicks) Problem BOLESSON (6692. B - Esperanto Lessons) Problem BOKO (6693. C - Karaoke) Problem BOMARBLE (6694. D - Playing with Marbles) Problem BOPERISH (6695. E - Publish of Perish) Problem GCJ101AB (6700. Make it Smooth) Problem CT101CC (6706. Making Chess Boards) Problem MBR (6709. Multiplying by Rotation ) Problem BLOCK (6711. Transform a sequence) Problem TWOPATHS (6717. Two Paths) Problem PFOLD (6720. Paper Fold) Problem GOLDG (6726. Goldbach graphs) Problem COEF (6731. Coeficientes)

28

1127. 1128. 1129. 1130. 1131. 1132. 1133. 1134. 1135. 1136. 1137. 1138. 1139. 1140. 1141. 1142. 1143. 1144. 1145. 1146. 1147. 1148. 1149. 1150. 1151. 1152. 1153. 1154. 1155. 1156. 1157. 1158. 1159. 1160. 1161. 1162. 1163. 1164. 1165. 1166. 1167. 1168. 1169. 1170. 1171. 1172. 1173.

Problem CT14E (6732. Camels) Problem CHEFMAY (6738. Nice Quadrangles) Problem SEQFUN (6767. Sequence Function) Problem HC (6772. Happy Coins) Problem DINONUM (6773. Dinostratus Numbers) Problem GSS7 (6779. Can you answer these queries VII) Problem ABSURD (6803. Absurd prices) Problem CHEATING (6804. Cheating or Not) Problem CATTACK (6805. Counter attack) Problem CAPCITY (6818. Capital City) Problem ASSIGN5 (6819. Yet Another Assignment Problem) Problem CFJUN21 (6823. Seller Bob) Problem CTFLAG (6824. Flag) Problem FPLAN (6825. Field Plan) Problem HACKING (6826. Hacking) Problem LMCONSTR (6827. Last Minute Construction) Problem LINEUP (6828. Lineup) Problem POLYNOM (6829. Polynomial) Problem SBETS (6830. Soccer Bets) Problem TBGAME (6831. Two Ball Game) Problem TOSCORE (6832. To Score or not to score) Problem CT10R3B (6851. Fence) Problem CT16E (6852. Fish) Problem ASISTENT (6860. Asistent) Problem WONKA1 (6885. Wonkas Oompa-Impa Dilemma) Problem PWSUM (6893. Power Sums) Problem MEPPERM (6895. Maximum Edge of Powers of Permutation) Problem SUB_PROB (6898. Substring Problem) Problem RPAR (6906. Raining Parabolas) Problem XYYHHTT (6917. Catch Sheep) Problem CT23E (6926. Tree game ) Problem CTOI10D2 (6949. PIN) Problem CTOI10D3 (6950. A HUGE TOWER) Problem CTOI10D1 (6951. MP3 Player) Problem CTOI09_1 (6956. IOI2009 Mecho) Problem PARTPAL (6957. Partial Palindrome) Problem INDEPCNT (6977. Odd Independent Sets) Problem PERMPATT (6978. Check 1324) Problem RNDORDER (6981. The Least Number) Problem ARRANGE2 (6985. Rearranging Digits) Problem SUMSLOPE (6986. Summing Slopes) Problem STJEPAN (6988. Beer Machines) Problem AVOIDSOS (6999. Avoiding SOS Grids) Problem VLATTICE (7001. Visible Lattice Points) Problem BUILDING (7002. Buildings) Problem ACAB (7010. Police Business) Problem CFPARTY (7015. Party)

29

1174. 1175. 1176. 1177. 1178. 1179. 1180. 1181. 1182. 1183. 1184. 1185. 1186. 1187. 1188. 1189. 1190. 1191. 1192. 1193. 1194. 1195. 1196. 1197. 1198. 1199. 1200. 1201. 1202. 1203. 1204. 1205. 1206. 1207. 1208. 1209. 1210. 1211. 1212. 1213. 1214. 1215. 1216. 1217. 1218. 1219. 1220.

Problem ZIGZAG (7019. Zig-Zag rabbit) Problem CPATTERN (7022. Cow Patterns) Problem KOLACI (7023. Cookies) Problem CT25C (7025. Roads in Berland) Problem CROBOTS (7034. Crashing Robots) Problem CRYPTON (7035. The Embarrassed Cryptographer) Problem NECKDEC (7050. Necklace Decomposition) Problem ADVEDIST (7099. Advanced Edit Distance) Problem BACKTPOL (7100. Back To The Polygon) Problem CANDN (7101. Charly And Nito) Problem DTWW (7102. Doing The Word Wrap) Problem EDDIST (7103. Edit Distance) Problem FTHEELF (7104. Feanor The Elf) Problem GK (7107. G Key) Problem HEPNUM (7108. Heptadecimal Numbers) Problem INDIPROG (7109. Indicator of progression) Problem HEADSHOT (7132. Headshot) Problem IOIGARD (7133. Garden 2005) Problem IOIPALIN (7150. Palindrome 2000) Problem IOIBOUND (7152. Boundary 2003) Problem CF25E (7155. Test) Problem EGYPIZZA (7169. Pizza) Problem AXIS (7184. Axis of Symmetry) Problem BYECAKES (7185. Bye Bye Cakes) Problem COUNTPAS (7186. Counting Pascal) Problem DINOSM (7187. Dinosaur Menace) Problem ESJAIL (7188. Escape from Jail) Problem FALTAENV (7189. Falta Envido) Problem GUESSTHE (7190. Guess the Number) Problem HEXBOARD (7191. Hexagonal Board) Problem INTEGMAX (7192. Integral Maximization) Problem CURSE (7193. The Pharaoh Curse) Problem CAL (7200. Strange Calendar) Problem BORW (7208. Black or White) Problem CLOSEST (7209. Closest Triplet) Problem DRAWM (7210. Draw Mountains) Problem ELASTIC (7211. Elastic Bands) Problem FINDSR (7212. Find String Roots) Problem CLOCKS (7216. The Clocks) Problem TRIKA (7217. Training for final) Problem GARBAGE (7230. Garbage Collection) Problem HOMEW (7231. Homework) Problem INVESORT (7232. Inversion Sort) Problem IPCELLS (7239. Cells) Problem PLYGRND (7240. Playground) Problem ROOKS (7248. Chess part1) Problem PERFUME (7249. Perfume)

30

1221. 1222. 1223. 1224. 1225. 1226. 1227. 1228. 1229. 1230. 1231. 1232. 1233. 1234. 1235. 1236. 1237. 1238. 1239. 1240. 1241. 1242. 1243. 1244. 1245. 1246. 1247. 1248. 1249. 1250. 1251. 1252. 1253. 1254. 1255. 1256. 1257. 1258. 1259. 1260. 1261. 1262. 1263. 1264. 1265. 1266. 1267.

Problem PBOARD (7250. Blocks for kids) Problem SUBLEX (7258. Lexicographical Substring Search) Problem LITE (7259. Light Switching) Problem NUMGAME (7260. Number Game) Problem DIGNUM (7264. Digital LED Number) Problem CNTTREE (7296. Trees Again) Problem GRIDCOIN (7297. Placing Coins on a Grid) Problem MULTQ3 (7299. Multiples of 3) Problem LCKYCONT (7301. Lucky Controller) Problem CHEFJUN (7322. Prime Pattern) Problem CHEFJUL (7323. Happy Days) Problem SHUFFLEN (7333. Shuffle Music) Problem SHUFFLE1 (7337. Shuffling) Problem ITERBIT (7356. Iterated Bitcount Function) Problem TREESUM (7363. Tree Sum) Problem MCOMP (7378. Manhattan Companies) Problem FUNFACT (7380. Factorial challenge) Problem ACTIV (7386. Activities) Problem PKA (7387. Airplane Parking) Problem PKD (7389. Rating Hazard) Problem PC8H (7402. Repair Depots) Problem MESS (7403. Messy Administration) Problem ONTIME (7404. Just on Time) Problem PANCAKES (7405. Delicious Pancakes) Problem BEENUMS (7406. Beehive Numbers) Problem CAMELOT (7408. Camelot) Problem DRAWQUAD (7409. Drawing Quadrilaterals) Problem ESCJAILA (7422. Escape from Jail Again) Problem FILRTEST (7423. File Recover Testing) Problem GIRLSNBS (7424. Girls and Boys) Problem HACKERS (7425. Hackers) Problem IMPUNITS (7426. Imperial Units) Problem JARA (7427. Jaras Legacy) Problem RANJAN02 (7430. Tower Of Hanoi - Revisited) Problem BIO1 (7486. Rooks) Problem FLIB (7487. Flibonakki) Problem LGLOVE (7488. LCM GCD Love) Problem SBACT (7489. Slow Growing Bacteria) Problem BIO (7490. Biology) Problem CF33C (7507. Wonderful Randomized Sum) Problem HAROWS (7555. A - Crazy Rows) Problem HASTOCK (7556. B - Stock Charts) Problem HAALPHA (7558. D - Alphabetomials) Problem HATEAM (7559. E - Football Team) Problem HARANGES (7560. F - Interesting Ranges) Problem LEXIPOS (7561. Lexicographic position) Problem HLP (7562. Help in organizing)

31

1268. 1269. 1270. 1271. 1272. 1273. 1274. 1275. 1276. 1277. 1278. 1279. 1280. 1281. 1282. 1283. 1284. 1285. 1286. 1287. 1288. 1289. 1290. 1291. 1292. 1293. 1294. 1295. 1296. 1297. 1298. 1299. 1300. 1301. 1302. 1303. 1304. 1305. 1306. 1307. 1308. 1309. 1310. 1311. 1312. 1313. 1314.

Problem HISIX (7563. Hi6) Problem IITD1 (7565. Another Sorting Algorithm) Problem IITD5 (7566. Expected Cycle Sums) Problem IITD4 (7567. Divisor Summation Powered) Problem YOKOF (7579. Power Calculus) Problem YOKOH (7581. The Best Name for Your Baby) Problem YOKOC (7583. Cubic Eight-Puzzle) Problem NUMOFPAL (7586. Number of Palindromes) Problem MISERMAN (7588. Wise And Miser) Problem PC8C (7589. Cave Crisis) Problem PC8F (7599. Optimal Strategy for the ICPC) Problem MLK (7600. Milk Trading) Problem CF36D (7602. New Game with a Chess Piece) Problem FIBFACT (7603. Fibonacci Factor) Problem DIVISER9 (7623. Divisors VI) Problem NE06D (7627. Driving Direction) Problem MATHS (7628. Mathematics) Problem BPORT (7629. Building Ports) Problem SHOPPERS (7630. SHOPPERS) Problem ARCHI (7632. Architecture) Problem RANJAN05 (7637. Road Map) Problem TELECOM (7666. Telecommunications) Problem PEBBLE (7668. Pebble Solver) Problem CPCRC1C (7676. Sum of Digits) Problem ELEC (7680. Electrical Engineering) Problem CSQUARE (7683. Powered and Squared) Problem FLWRS (7685. Flowers) Problem HOMO (7691. Homo or Hetero) Problem CHEM (7692. Chemistry) Problem ENVIRON (7693. Environmental Engineering) Problem CENCRY (7696. Encryption) Problem CIVIL (7704. Civil Engineering) Problem JZPCIR (7709. Jumping Zippy) Problem COMDIV (7718. Number of common divisors) Problem HPYNOS (7733. Happy Numbers I) Problem BOI7ESC (7737. Escape) Problem BOI7SOU (7739. Sound) Problem BOI7FEN (7740. Fence) Problem BOI7SEQ (7741. Sequence) Problem OLOLO (7742. Onotole needs your help) Problem HPYNOSII (7753. Happy Numbers II) Problem HLPRSRCH (7772. Help a researcher) Problem ANARC09I (7776. Kind of a blur) Problem ANARC09J (7777. National Treasure) Problem ANARC09H (7778. Land Division) Problem ANARC09G (7779. Stock Chase) Problem LLCA (7782. Largest Labeled Common Ancestor)

32

1315. 1316. 1317. 1318. 1319. 1320. 1321. 1322. 1323. 1324. 1325. 1326. 1327. 1328. 1329. 1330. 1331. 1332. 1333. 1334. 1335. 1336. 1337. 1338. 1339. 1340. 1341. 1342. 1343. 1344. 1345. 1346. 1347. 1348. 1349. 1350. 1351. 1352. 1353. 1354. 1355. 1356. 1357. 1358. 1359. 1360. 1361.

Problem COMFUNC (7783. Commuting Functions) Problem DEFKIN (7804. Defense of a Kingdom) Problem KITROB (7805. Kitchen Robot) Problem LPRISON (7807. The Lucky Prisoner) Problem COWPIC (7809. Cow Photographs ) Problem TREEISO (7826. Tree Isomorphism) Problem JZPSTA (7851. Stacks of Zippy) Problem ADV04A1 (7857. Tower Game (Hard)) Problem ADV04B1 (7859. Upper Right King (Hard)) Problem ADV04C (7860. Deal or No Deal) Problem ADV04D (7861. UFO) Problem ADV04E (7862. Prisoner of Benda) Problem ADV04F1 (7864. Four Chips (Hard)) Problem ADV04G1 (7866. Regular expressions (Hard)) Problem ADV04H (7868. Join) Problem ADV04J (7870. Invisible point) Problem ADV04K (7874. Calculator) Problem ADV04L (7875. Miles and kilometers) Problem C1LJUTNJ (7881. Ljutnja) Problem C1TABOVI (7882. Tabovi) Problem C2CRNI (7884. Crni) Problem ADV04I1 (7886. Boards (Hard)) Problem SPFIBO (7891. Fibonacci Sequence) Problem SKYLINE (7897. Skyline) Problem FINDPATH (7909. CALCULATE PATH FOR JERRY) Problem OSPROB1 (7934. Operating System Problems (Task Scheduling)) Problem MULPAL (7960. Multiplicative Palindrome) Problem ACPC10G (7969. A Knights Tale) Problem ACPC10H (7970. Jumping Beans) Problem ACPC10I (7971. The Cyber Traveling Salesman) Problem ACPC10F (7972. World of cubes) Problem ACPC10E (7973. Sometimes, a penalty is good!) Problem ACPC10A (7974. Whats Next) Problem ACPC10D (7975. Tri graphs) Problem ACPC10B (7976. Sum the Square) Problem FIBOSUM (8001. Fibonacci Sum) Problem HORRIBLE (8002. Horrible Queries) Problem TTOP (8004. Tree Topology) Problem SOCIALNE (8042. Possible Friends) Problem IMMERSED (8044. Fantastic Discovery) Problem AMR10A (8055. Playground) Problem AMR10B (8056. Regex Edit Distance) Problem AMR10C (8057. Square Free Factorization) Problem AMR10D (8058. Soccer Teams) Problem AMR10E (8059. Stocks Prediction) Problem AMR10G (8061. Christmas Play) Problem AMR10H (8062. Shopping Rush)

33

1362. 1363. 1364. 1365. 1366. 1367. 1368. 1369. 1370. 1371. 1372. 1373. 1374. 1375. 1376. 1377. 1378. 1379. 1380. 1381. 1382. 1383. 1384. 1385. 1386. 1387. 1388. 1389. 1390. 1391. 1392. 1393. 1394. 1395. 1396. 1397. 1398. 1399. 1400. 1401. 1402. 1403. 1404. 1405. 1406. 1407. 1408.

Problem AMR10I (8063. Dividing Stones) Problem AMR10J (8064. Mixing Chemicals) Problem CIRU (8073. The area of the union of circles) Problem NUMG (8074. God of Number Theory) Problem SEQN (8075. Sequence) Problem JZPGYZ (8093. Sevenk Love Oimaster) Problem SPQUEUE (8096. Queue) Problem IOIISL08 (8097. Islands) Problem TABLE (8099. Crashs number table) Problem SHLIGHTS (8100. Shifting Lights) Problem KFRIENDS (8104. Friendly Knights) Problem DPMAX (8105. Dot Product Maximization) Problem ACPC10C (8106. Normalized Form) Problem POLYU (8108. POLYU) Problem CIRUT (8119. CIRU2) Problem SKY (8129. Sky Lift) Problem STREETR (8132. Street Trees) Problem CHAIR (8139. Chairs) Problem JZPEXT (8177. Beautiful numbers EXTREME) Problem BUREAU (8184. Bureaucracy) Problem CIRCSCR (8189. Circles On A Screen) Problem XMAX (8217. XOR Maximization) Problem NSUBSTR (8222. Substrings) Problem NFACTOR (8238. N-Factorful) Problem EMILABC (8263. Big Pyramid) Problem ZEROCNT (8265. Zero Count) Problem PSTR (8277. Number of Prime Strings) Problem INTCOMB (8281. Combination Of Integers) Problem DIST (8282. Distance) Problem NONDEC (8283. Non-Decreasing Numbers) Problem WEIGHT (8284. Weighted Sum) Problem RECTMAT (8285. Rectangles in a Matrix) Problem MATCH (8286. Perfect Matching) Problem FASTFOOD (8288. Fast Food Restaurant) Problem WINGOLD (8316. Win gold medal ) Problem SIGNGAME (8317. Red Balls) Problem PLAYSIGN (8318. color the balls) Problem GLJIVE (8319. GLJIVE) Problem SCROLL (8320. Spreadsheet scrolling) Problem CHOCDIST (8321. Chocolate distribution) Problem TRIEQUAL (8323. Triangle equality) Problem MILPATR (8324. Military patrol) Problem PARTPLNE (8325. Partitioning the plane) Problem LEAKCONT (8326. Leaky containers) Problem PROGPROG (8327. Progressive progressions) Problem MOVEBOOK (8328. Move the books) Problem ROADTRIP (8329. Road trip)

34

1409. 1410. 1411. 1412. 1413. 1414. 1415. 1416. 1417. 1418. 1419. 1420. 1421. 1422. 1423. 1424. 1425. 1426. 1427. 1428. 1429. 1430. 1431. 1432. 1433. 1434. 1435. 1436. 1437. 1438. 1439. 1440. 1441. 1442. 1443. 1444. 1445. 1446. 1447. 1448. 1449. 1450. 1451. 1452. 1453. 1454. 1455.

Problem GNTFNTN (8330. Giant fountain) Problem SSTRCITS (8331. Sister cities) Problem SKISLOPE (8332. Ski slopes) Problem PLCNMGME (8333. Place-name game) Problem ENUMRTNL (8334. Enumeration of rationals) Problem CNTTEAMS (8335. Counting the teams) Problem BRODOVI (8349. BRODOVI) Problem MIDO (8351. KOSARK) Problem CCHESS (8363. COSTLY CHESS) Problem PRISMSA (8371. TRIANGULAR PRISM) Problem TSUM (8372. Triple Sums) Problem PARKET1 (8374. PARKET) Problem BALL (8391. The Ball) Problem YOUTUBE (8392. Youtube) Problem QUADRATE (8398. Quadratic Equation) Problem TEMPLEQ (8406. Temple Queues) Problem CANDYSTN (8407. Candies and Milestones) Problem MNMXPATH (8408. Min Max 01 Path) Problem FAVSUBS (8409. Favorite Sub Hair) Problem SNAKYNUM (8410. Snaky Numbers) Problem SQUA_REV (8418. Revenge of the squares) Problem BTCODE_A (8419. Traversing Grid) Problem BTCODE_B (8420. Finding Minimum) Problem BTCODE_C (8421. Fun With Inequalities) Problem BTCODE_D (8422. Maximum Profit) Problem BTCODE_E (8423. Recover Polynomials) Problem BTCODE_F (8424. Life Game) Problem BTCODE_G (8425. Coloring Trees) Problem BTCODE_H (8426. Trie Expectation) Problem BTCODE_I (8427. Permutation Game) Problem BTCODE_J (8428. Grid Tiling) Problem BTCODE_K (8429. Array Sorting) Problem SQUAREV1 (8433. Revenge of the squares (variation)) Problem KOLICA (8434. Kolica) Problem NOVICE43 (8442. Problem 3) Problem PLOT1 (8449. Plotting functions (variation)) Problem PROBLEM4 (8456. PRIMITIVEROOTS) Problem AVDM (8461. Adventure in Moving) Problem BARN (8462. Barn Allocation) Problem GPA1 (8467. GRADE POINT AVERAGE) Problem POCALC1 (8478. Ancient Pocket Calculator) Problem PHONMESS (8491. Messy Phone List) Problem MAXSUB (8495. Maximum Subset of Array) Problem NOSQ (8496. No Squares Numbers) Problem NACCI (8505. Nacci Fear) Problem PSWITCH (8507. Party Switching) Problem POCALC2 (8542. Modern Pocket Calculator)

35

1456. 1457. 1458. 1459. 1460. 1461. 1462. 1463. 1464. 1465. 1466. 1467. 1468. 1469. 1470. 1471. 1472. 1473. 1474. 1475. 1476. 1477. 1478. 1479. 1480. 1481. 1482. 1483. 1484. 1485. 1486. 1487. 1488. 1489. 1490. 1491. 1492. 1493. 1494. 1495. 1496. 1497. 1498. 1499. 1500. 1501. 1502.

Problem MAIN72 (8545. Subset sum) Problem MAIN73 (8546. Manoj and Pankaj ) Problem MAIN74 (8547. Euclids algorithm revisited ) Problem MAIN75 (8549. BST again) Problem LSQF (8550. Longest Square Factor) Problem ABCD (8551. Colours A, B, C, D) Problem LINQSOLV (8558. Linear Equation Solver) Problem FOUROW (8574. Four in a row) Problem REVSEQ (8578. Reverse the sequence) Problem NPOWM (8583. Garden) Problem PRIME (8586. Factorial factorisation) Problem PRIMPERM (8591. Prime Permutations) Problem TAILS (8594. Tails all the way ) Problem WAGE (8596. Wood, Axe and Grass) Problem TRAVERSE (8598. Traverse through the board) Problem NY10E (8611. Non-Decreasing Digits) Problem NY10A (8612. Penney Game) Problem NY10B (8624. Nim-B Sum) Problem NY10C (8625. Just The Simple Fax) Problem NY10D (8626. Show Me The Fax) Problem NY10F (8627. I2C) Problem NWERC10G (8628. Selling Land) Problem NWERC10H (8629. Stock Prices) Problem ALIENS1 (8651. Alien arithmetic) Problem CHEFFEB (8661. Bogosort) Problem CHEFMAR (8663. Squares Game) Problem ITRIX_C (8666. Maximum - Profit -- Version II) Problem ITRIX_D (8667. Board-Queries) Problem ITRIX_E (8668. THE BLACK AND WHITE QUEENS) Problem MAXLN (8670. THE MAX LINES) Problem GAME2 (8720. Looks like Nim - but it is not) Problem CLOPPAIR (8725. Closest Point Pair) Problem MAKETREE (8728. Hierarchy) Problem BFIT (8732. Best Fit) Problem CHARLIE (8734. Charlie and the Chocolate Factory) Problem CUBEND (8735. Suffix Of Cube) Problem NSUBSTR2 (8747. Substrings II) Problem WORD (8750. Wordplay) Problem MAIN8_C (8756. Shake Shake Shaky) Problem MAIN8_D (8757. Coing tossing ) Problem MAIN8_E (8758. Cover the string) Problem SKIING (8759. Alpine Skiing) Problem STRDIST2 (8769. String distance) Problem SILVER (8785. Cut the Silver Bar) Problem DOMINO1 (8786. The Longest Chain of Domino Tiles) Problem DYNALCA (8791. Dynamic LCA) Problem SPOINTS (8793. Separate Points)

36

1503. 1504. 1505. 1506. 1507. 1508. 1509. 1510. 1511. 1512. 1513. 1514. 1515. 1516. 1517. 1518. 1519. 1520. 1521. 1522. 1523. 1524. 1525. 1526. 1527. 1528. 1529. 1530. 1531. 1532. 1533. 1534. 1535. 1536. 1537. 1538. 1539. 1540. 1541. 1542. 1543. 1544. 1545. 1546. 1547. 1548. 1549.

Problem SWJAM (8794. Swimming Jam) Problem TWENTYQ (8795. Twenty Questions) Problem CUBARTWK (8796. Cubist Artwork) Problem MRAVOGRA (8816. Mravograd) Problem OKRET (8820. Okret) Problem SEQ7 (8836. Yet Another Sequence Problem) Problem LCDS (8839. Longest Common Difference Subsequence) Problem AVARY (8841. Avaricious Maryanna) Problem BWORK (8842. Boring Homework) Problem COMPLETE (8843. Complete the Set) Problem DETECT (8844. Detection of Extraterrestrial) Problem TENNIS (8845. Entertainment) Problem MAHJONG (8846. Fudan Extracurricular Lives) Problem HERBICID (8848. Herbicide) Problem IMITATE (8849. Imitation) Problem JUICE (8850. Juice Extractor) Problem PRATA (8869. Roti Prata) Problem GNUM (8886. Guess number!) Problem DOUTI (8894. Double Time) Problem POCRI (8895. Power Crisis) Problem PATT (8896. Pattern Matching) Problem PROBOR (8910. Probablistic OR) Problem VILLAGES (8916. Villages by the River) Problem PLUSEVI (8917. How Many Plusses) Problem PAAAARTY (8930. Party!) Problem GRIDPNTS (8945. Grid points (speed variation)) Problem XIXO (8951. brownie) Problem THRBL (8952. Catapult that ball) Problem KOICOST (8980. Cost) Problem KOIREP (8982. Representatives) Problem KOILINE (8985. Line up) Problem FUPRCO (8989. Funny programming contest) Problem GUESSLNK (8991. Number Guessing Game 2) Problem SALTOS (8992. A los saltos) Problem LQDCANDY (8995. CANDY) Problem KITEPRBL (9000. Bob and his new kite factory) Problem MAXMATCH (9012. Maximum Self-Matching) Problem KVALTWR (9030. Bob and his towers) Problem CUBEFR (9032. Cube Free Numbers) Problem TOHU (9034. Help Tohu) Problem BISHOP2 (9038. Chessboard Billiard) Problem TUG (9040. Tug of War) Problem HQNP (9042. HQNP Incomputable) Problem HANDS (9046. Clock Hands) Problem TOHU2 (9050. Tohu again) Problem FREQ2 (9055. Most Frequent Value) Problem XXXXXXXX (9066. Sum of Distinct Numbers)

37

1550. 1551. 1552. 1553. 1554. 1555. 1556. 1557. 1558. 1559. 1560. 1561. 1562. 1563. 1564. 1565. 1566. 1567. 1568. 1569. 1570. 1571. 1572. 1573. 1574. 1575. 1576. 1577. 1578. 1579. 1580. 1581. 1582. 1583. 1584. 1585. 1586. 1587. 1588. 1589. 1590. 1591. 1592. 1593. 1594. 1595. 1596.

Problem LIGHTIN (9070. Lightning Conductor) Problem HABLU (9076. Hablu and Bablu) Problem INCEST (9081. Snail family problems) Problem JRNTMRS (9084. Journey to Mars) Problem JZPFOR (9086. Formula 3D) Problem MGCSCLS (9096. Bob and magical scale) Problem NOVICE65 (9097. Derangements HARD) Problem LCS3 (9098. Long Common Subsequence) Problem NOVICE63 (9103. Special Numbers) Problem NOVICE62 (9104. Match the words) Problem GCPC11A (9117. Faculty Dividing Powers) Problem GCPC11B (9118. Genetic Fraud) Problem GCPC11C (9119. Indiana Jones and the lost Soccer Cup) Problem GCPC11D (9120. Magic Star) Problem GCPC11E (9121. Magical Crafting) Problem GCPC11F (9122. Diary) Problem GCPC11G (9123. Security Zone) Problem GCPC11H (9124. Sightseeing) Problem GCPC11I (9125. Suiting Weavers) Problem GCPC11J (9126. Time to live) Problem PYRSUM (9137. Pyramid Sums) Problem PYRSUM2 (9138. Pyramid Sums 2) Problem LEGRENDS (9161. Legendre symbol) Problem TORNJEVI (9185. TORNJEVI) Problem TREEMAZE (9190. Perfect Maze) Problem SPEED (9199. Circular Track) Problem MAFBOI08 (9213. Mafia) Problem BHAT007 (9219. Nikhil Problem) Problem AHORCADO (9242. B Beware, the end of the world) Problem PUBLICAT (9255. Publication) Problem PERFECTR (9260. Perfect Road) Problem DCD (9331. DCD) Problem TETRAHED (9334. Point in tetrahedron) Problem ARBITRAG (9340. Arbitrage) Problem SFLIP (9367. Segment Flip) Problem LANDFILL (9378. Landfill) Problem CARNIVAL (9382. Complan Carnival) Problem MAIN111 (9385. Strictly not a Prime) Problem MAIN112 (9386. Re-Arrange II) Problem MAIN113 (9387. Special String) Problem GAME31 (9430. The game of 31) Problem BUZZW (9433. Buzzwords) Problem NEWH (9434. New Horizons) Problem ADDMUL (9440. To Add or to Multiply) Problem YALOP (9443. Trial of Doom) Problem BLOCKDRO (9444. Block Drop) Problem CLONES (9445. Attack of the Clones)

38

1597. 1598. 1599. 1600. 1601. 1602. 1603. 1604. 1605. 1606. 1607. 1608. 1609. 1610. 1611. 1612. 1613. 1614. 1615. 1616. 1617. 1618. 1619. 1620. 1621. 1622. 1623. 1624. 1625. 1626. 1627. 1628. 1629. 1630. 1631. 1632. 1633. 1634. 1635. 1636. 1637. 1638. 1639. 1640. 1641. 1642. 1643.

Problem SHORTCIR (9446. Shortest Circuit Evaluation) Problem GENETICS (9447. Genetics) Problem SWARM (9448. Swarm of Polygons) Problem GHOSTS (9458. Ghosts having fun) Problem THREETW1 (9459. Connecting three towns (variation)) Problem ANARC07J (9489. Johny Hates Math) Problem ADFRUITS (9493. Advanced Fruits) Problem ZSUM (9494. Just Add It) Problem WORKB (9503. Working in Beijing) Problem PAINTWAL (9504. Paint on a Wall) Problem DSUBTREE (9505. Distinct Subtrees) Problem DIST2 (9506. Jimmys Travel Plan) Problem MARIO2 (9507. Mario and Mushrooms) Problem AND (9508. Magic Bitwise AND Operation) Problem CYLINDES (9509. Shortest Path on a Cylinder) Problem ADSPROP (9510. Ads Proposal) Problem PUZZLE24 (9511. 24-Puzzle) Problem BOMB2 (9512. Bombing) Problem TETRISGM (9513. Game) Problem HUNT1 (9515. Dwarven Snipers Hunting) Problem XOREQ (9516. XOR Equations) Problem UNLOCK (9517. Unlock the Cellphone) Problem LCM (9518. The Time of Day) Problem DSUBMTR (9519. Distinct Submatrices) Problem TANKS (9520. Tanks) Problem CIPHERJ (9525. Cipher) Problem DEPARTJ (9527. Department) Problem JTRIP (9528. Johns Trip) Problem MAYCA (9529. Maya Calendar) Problem TRANSJ (9532. Transportation) Problem JZPLIT (9534. Turn on the lights) Problem JZPLIT2 (9535. Turn on the lights 2) Problem DCES (9543. Dynamic Congruence Equation System) Problem DPAIR (9547. Counting d-pairs) Problem PAIRSUM (9569. Sum of Pairwise Products) Problem STRCOUNT (9570. Counting binary strings) Problem DYNACON2 (9576. Dynamic Graph Connectivity) Problem DYNACON1 (9577. Dynamic Tree Connectivity) Problem PRIMEZUK (9587. The Prime conjecture) Problem ACANVAS (9636. A Canvas Building) Problem BANDW (9637. Black and White) Problem CIRCUITS (9638. Circuits) Problem EQUI (9640. Equilibrium) Problem FBRIDGES (9641. Factory of Bridges) Problem GETFAST (9642. Getting There Fast) Problem HEISLAZY (9643. He is Lazy) Problem IMPER (9644. Imperialism)

39

1644. 1645. 1646. 1647. 1648. 1649. 1650. 1651. 1652. 1653. 1654. 1655. 1656. 1657. 1658. 1659. 1660. 1661. 1662. 1663. 1664. 1665. 1666. 1667. 1668. 1669. 1670. 1671. 1672. 1673. 1674. 1675. 1676. 1677. 1678. 1679. 1680. 1681. 1682. 1683. 1684. 1685. 1686. 1687. 1688. 1689. 1690.

Problem JOCTENIS (9645. Joy of CompuTenis) Problem TRIPINV (9650. Mega Inversions) Problem ROBOTGRI (9652. Robots on a grid) Problem ELEVTRBL (9655. Elevator Trouble) Problem ZTC (9685. Zombies Treasure Chest) Problem YUMMY (9686. Yummy Triangular Pizza) Problem XC (9687. Xavier is Learning to Count) Problem VBWORK (9689. Very Boring Homework) Problem UQAS (9690. Universal Question Answering System) Problem TQ (9691. Triangles and Quadrangle) Problem CAKE4 (9692. Share the Cakes) Problem REVFIB (9693. Revenge of Fibonacci) Problem QB (9694. Quelling Blade) Problem CODESPTA (9721. 2s Complement) Problem CODESPTB (9722. Insertion Sort) Problem CODESPTC (9723. Card Shuffling) Problem CODESPTD (9725. Queens on a Board) Problem HACKRNDM (9734. Hacking the random number generator) Problem CODESPTE (9746. Bytelandian Tours) Problem CODESPTF (9748. Palindromes) Problem CODESPTG (9749. Cliques) Problem CODESPTH (9750. Polygon Diagonals) Problem CODESPTI (9751. Repairing Roads) Problem TUPLEDIV (9753. Tuple Division) Problem SCPC11D (9754. Egypt) Problem SCPC11A (9755. Grey Area) Problem SCPC11B (9756. Alaska) Problem SCPC11F (9759. GO) Problem SCPC11G (9760. Indomie) Problem SCPC11H (9761. Dolls) Problem FACEFRND (9788. Friends of Friends) Problem BEHAPPY (9805. Be Awesome As Barney Stinson) Problem WPC4C (9817. Shortcut) Problem WPC4F (9820. Through the troops) Problem MIFF (9832. Matrix inverse) Problem GAME3 (9842. Yet Another Fancy Game) Problem GLASS (9856. The Glazier) Problem EIGHT (9857. Eight Directions Crossword) Problem WALK1 (9858. tef and Barica) Problem GLASS2 (9860. The Glazier 2) Problem HOTELS (9861. Hotels Along the Croatian Coast) Problem REMOVE (9862. Help the Airline Company) Problem NWERC11A (9887. Binomial coefficients) Problem NWERC11B (9888. Bird tree) Problem NWERC11C (9889. Movie collection) Problem NWERC11D (9890. Piece it together) Problem NWERC11E (9891. Please, go first)

40

1691. 1692. 1693. 1694. 1695. 1696. 1697. 1698. 1699. 1700. 1701. 1702. 1703. 1704. 1705. 1706. 1707. 1708. 1709. 1710. 1711. 1712. 1713. 1714. 1715. 1716. 1717. 1718. 1719. 1720. 1721. 1722. 1723. 1724. 1725. 1726. 1727. 1728. 1729. 1730. 1731. 1732. 1733. 1734. 1735. 1736. 1737.

Problem NWERC11F (9892. Pool construction) Problem NWERC11G (9893. Smoking gun) Problem NWERC11H (9894. Tichu) Problem NWERC11I (9895. Tracking RFIDs) Problem NWERC11J (9896. Train delays) Problem PONY1 (9916. Help Dr Whooves) Problem ABCPATH (9921. ABC Path) Problem ALICE (9934. Alice and Bob) Problem BC (9935. Break the Chocolate) Problem CGW (9936. Construct the Great Wall) Problem DISNEY (9938. Disney Fastpass) Problem EC (9939. Eliminate the Conflict) Problem FNINJA (9940. Fruit Ninja) Problem GRE (9941. GRE Words) Problem HOLI (9942. Holiday Accommodation) Problem ISAB (9943. Isabella Message) Problem JITU (9944. Ji-Tu Problem) Problem WILLITST (9948. Will it ever stop) Problem IQTEAM (9950. IQ Team) Problem GUANGGUN (9952. 111...1 Squared) Problem PIBO (9964. Fibonacci vs Polynomial) Problem PWORDS (9967. Playing with Words) Problem MCLB (9968. Magic Crystals and Laser Beams) Problem RDNWK (9969. Road Network) Problem EGYPAR (9970. The Egyptian Parliament) Problem ACHESS (9971. Adventurous Chess Masters) Problem SKEY (9972. The SKey) Problem PROSCORE (9973. Problem Set Score) Problem MENMARS (9974. Men From Mars) Problem FSEQ (9975. No Stories Any More!) Problem DISTX (9985. Distance) Problem POWTOW (10050. Power Tower City) Problem KOMPICI (10069. Kompii) Problem TRICKTRT (10070. Trick or Treat) Problem RESTAURN (10071. Working at the Restaurant) Problem LIGHTS2 (10072. Lights) Problem DARTS (10073. Darts) Problem GENETIC2 (10074. Genetics) Problem GRAVEYRD (10075. Haunted Graveyard) Problem SLALOM2 (10076. Slalom) Problem ROUTING (10077. Routing) Problem HAPPYTL (10078. Happy Telephones) Problem STAMMER (10079. Stammering Aliens) Problem LAWNMWR (10080. Lawn Mower) Problem PERIODIC (10081. Periodic Points) Problem CMPANS (10082. Comparing Answers) Problem FAKESCOR (10084. Fake Scoreboard)

41

1738. 1739. 1740. 1741. 1742. 1743. 1744. 1745. 1746. 1747. 1748. 1749. 1750. 1751. 1752. 1753. 1754. 1755. 1756. 1757. 1758. 1759. 1760. 1761. 1762. 1763. 1764. 1765. 1766. 1767. 1768. 1769. 1770. 1771. 1772. 1773. 1774. 1775. 1776. 1777. 1778. 1779. 1780. 1781. 1782. 1783. 1784.

Problem PALINDNA (10085. Palindromic DNA) Problem JMPMNKEY (10086. Jumping Monkey) Problem SENSORNT (10087. Sensor Network) Problem ASSEMBLY (10088. Assembly Line) Problem LOCKKEY (10089. Locks and Keys) Problem DICE (10091. Three-sided Dice) Problem PRTYNGHT (10092. Party Night) Problem CAPPIZZA (10095. Caper Pizza) Problem LIGHTS3 (10096. Lights (Extreme)) Problem ALPHSOUP (10105. Alphabet Soup) Problem COIN (10106. Coin Collecting) Problem DONUT (10107. Cybercrime Donut Investigation) Problem BALLOT (10108. Distributing Ballot Boxes) Problem GSM (10109. Game, Set and Match) Problem GUESSNM2 (10110. Guess the Numbers) Problem PARSUMS (10111. Nonnegative Partial Sums) Problem REVIEW (10112. Peer Review) Problem REGPOLYG (10113. Regular Convex Polygon) Problem RMTLAND (10114. Remoteland) Problem TANDV (10128. Treasures and Vikings) Problem STRAZA (10141. STRAZA) Problem BCAKE (10145. Birthday Cake) Problem PUCMM025 (10186. Divisor Digits) Problem TRANSFER (10210. After Party Transfers) Problem AMR11A (10228. Magic Grid) Problem AMR11B (10229. Save the Students) Problem AMR11C (10230. Robbing Gringotts) Problem AMR11D (10231. Wizarding Duel) Problem AMR11E (10232. Distinct Primes) Problem AMR11F (10233. Magical Bridges) Problem AMR11H (10235. Array Diversity) Problem AMR11I (10236. Generations) Problem AMR11J (10237. Goblin Wars) Problem ACPC11B (10239. Between the Mountains) Problem ACPC11C (10240. Circleland) Problem ACPC11D (10242. Dice on a Board) Problem METEORS (10264. Meteors) Problem DIVIDEKR (10265. Subdivision of the kingdom) Problem TEMPERAT (10270. Temperature) Problem ALLIZWEL (10283. ALL IZZ WELL) Problem WTK (10285. Why this kolaveri di) Problem DOTAA (10286. DOTA HEROES) Problem SHELL (10292. Shell game) Problem FANCY (10293. FANCY NUMBERS) Problem JUMPY (10301. A jumpy cycle) Problem CONCAVE (10312. Concave quadrilaterals) Problem SOLDIERS (10334. SOLDIERS)

42

1785. 1786. 1787. 1788. 1789. 1790. 1791. 1792. 1793. 1794. 1795. 1796. 1797. 1798. 1799. 1800. 1801. 1802. 1803. 1804. 1805. 1806. 1807. 1808. 1809. 1810. 1811. 1812. 1813. 1814. 1815. 1816. 1817. 1818. 1819. 1820. 1821. 1822. 1823. 1824. 1825. 1826. 1827. 1828. 1829. 1830. 1831.

Problem DISTO (10346. Streets of distortion) Problem CTSTRING (10354. Count Strings) Problem COINTOSS (10355. Coin Tosses) Problem CODEIT03 (10366. Play with Dates) Problem ABA12B (10376. String Factorization!) Problem MECGROUP (10377. project groups) Problem CAM5 (10380. prayatna PR) Problem DICT (10381. Search in the dictionary!) Problem ABA12C (10394. Buying Apples!) Problem ABA12D (10395. Sum of divisors!) Problem CONGA (10399. Conga line) Problem ALIEN (10401. Aliens at the train) Problem ABA12E (10405. Shooting the balloons!) Problem DRACULA (10415. Dracula) Problem VHELSING (10416. Van Helsings gun) Problem POLISH (10419. Polish Language) Problem IOPC1200 (10420. Hardware upgrade) Problem SNIPE (10421. Run, Snipe, Run) Problem IOPC1201 (10422. Rubiks cube) Problem TOPOLAND (10424. To Poland) Problem SECSYS (10425. Security System) Problem IOPC1202 (10437. Quadrilaterals) Problem IOPC1203 (10438. Crazy texting) Problem WALKROBO (10439. Walking Robot) Problem FRNDS (10440. Friends) Problem CADYDIST (10442. Candy Distribution) Problem BRDGS (10443. Bridges) Problem CODING2 (10444. Coding) Problem SICRANO (10446. Sicrano) Problem CONTCITY (10447. Contaminated City) Problem RESOURCE (10449. Resource Management) Problem AMOEBA (10450. Amoeba) Problem STUN (10451. Stun Boosting) Problem CAPRICA (10452. Caprica Cities) Problem SPRING (10453. Spring Loaded) Problem GREENLAN (10454. Greens Land) Problem IOPC1204 (10460. A function over factors) Problem IOPC1205 (10461. The magical escape) Problem PAREN (10463. COUNT PAREN) Problem RE1 (10464. Reverse Engineering) Problem OTOY1 (10465. One Theorem, One Year) Problem EALP1 (10466. Enough of analyzing, lets play) Problem ALIEN2 (10471. Aliens at the train, again!) Problem IOPC1206 (10476. Fair bases) Problem IOPC1207 (10477. GM plants) Problem HAYBALE (10500. Haybale stacking) Problem VIDEO (10502. Video game combos)

43

1832. 1833. 1834. 1835. 1836. 1837. 1838. 1839. 1840. 1841. 1842. 1843. 1844. 1845. 1846. 1847. 1848. 1849. 1850. 1851. 1852. 1853. 1854. 1855. 1856. 1857. 1858. 1859. 1860. 1861. 1862. 1863. 1864. 18