C++ Notes - MIT LecturesSource file (—Preprocessor—> Processed Code)(C++) —Compiler—> Object File -Libraries—Linker—>Executable—OS—> Program in Memory

Token type

KeywordsWords with special meaning to the compiler int, double, for, auto

IdentifiersNames of things that are not built into the language cout, std, x, myFunction

LiteralsBasic constant values whose value is specified directly in the source code

"Hello, world!", 24.3,0, ’c’

OperatorsMathematical or logical oper ations +, -, &&, %, <<

Punctuation/SeparatorsPunctuation defining the structure of a program {}(),;

WhitespaceSpaces of various sorts; ig nored by the compiler Spaces, tabs, newlines, com ments

cin >> - data being input into a value cout << - data being output into a value

Conditionals

use if statements and switch-case statements

Operator

> Greater than>= Greater than or equal to< Less than<= Less than or equal to== Equal to!= Not equal to

Operator

&& and|| or! not

Examples using logical operators (assume x = 6 and y = 2):

!(x > 2) → false(x > y) && (y > 0) → true (x < y) && (y > 0) → false (x < y) || (y > 0) → true

IF STATEMENTS

#include <iostream> using namespace std;

int main() {int x = 6;int y = 2;

if(x > y) cout << “x is greater than y\n”;

else if(y > x) cout << “y is greater than x\n”;

else cout << “x and y are equal\n”;

return 0;}

SWITCH-CASE STATEMENTS

#include <iostream>using namespace std;

int main() {int x = 6;

switch(x) { case 1: cout << “x is 1\n”; break; case 2: case 3: cout << "x is 2 or 3"; break; default: cout << "x is not 1, 2, or 3";

}

return 0;}

LOOPS

does certain actions while a condition is being met, infinite

>> Will say x is 10. Will keep adding 1 to x as long as x is < 10. once greater, will spit out the message

if: 1 or noneif-else statements: 1 has to be trueif-else-if: 1 or noneif-else-if-else: 1 has to be true

First gets an expression (in this case x, which is 6). Compares it to the first case, but x is not 1, so moves onSecond case, x is not 2 or 3, so moves onNo other options so goes to the default, which spits “x is not 1, 2, or 3”

#include <iostream>using namespace std;

int main() {int x = 0;

while(x < 10) x = x + 1;

cout << “x is “ << x << “\n”;

return 0;}

Variation of a loop. Will do statements 1 and 2 at least once as long as the condition is being met. Combined with above, will keep doing until x is not less than 10.

FOR

for loop is a loop that addresses change of a function of object.first part is the expression, second part is the while, third is positive or negative change

Here is the expression and variable, x =0. This for loop will document all instances x is less than 10 and spit it out with the formula x + 1. So users will see, 0-9

NESTED CONTROL STATEMENTS

do{statement1statement2... }while(condition);

for(initialization; condition; incrementation){ statement1 statement2 ...

1 #include <iostream>2 using namespace std;34 int main() {56 int x = 0;7 for(; x < 10; x = x + 1)8 cout << x << “\n”;9

#include <iostream> using namespace std;

int main() {

for(int x = 0; x < 10; x = x + 1) cout << x << “\n”;

return 0;}

#include <iostream>using namespace std;

int main() {

int x = 0;while(x < 10) {

cout << x << “\n”;x = x + 1;

}

#include <iostream> using namespace std;

int main() {int x = 6;int y = 0;if(x > y) {

cout << (“x is greater than y\n”;if (x == 6)

cout <<“x is equal to 6\n”;else

cout << “x is not equal to 6\n”;

} elsecout << “x is not greater than y\n”;

return 0;}

#include <iostream>using namespace std;

int main() {for(int x = 0; x < 4; x = x + 1) {

for(int y = 0; y < 4; y = y + 1) cout << y; cout << “\n”;

}return 0; }