4
What we will do today 1.You’ll try to write a recursive function to solve a simple problem 2.We’ll return to the count number of “a”s example from the previous day, and I’ll explore it a bit more 3.I’ll discuss an alternative recursive string function 4.I’ll discuss the “natural” recursive structure of files and directories, and go through a example with that 5.You will also write a recursive function with files and directories 6.If we have time: even more practice with recursive functions

What we will do today

  • Upload
    hamish

  • View
    35

  • Download
    2

Embed Size (px)

DESCRIPTION

What we will do today. You’ll try to write a recursive function to solve a simple problem We’ll return to the count number of “ a”s example from the previous day, and I’ll explore it a bit more I’ll discuss an alternative recursive string function - PowerPoint PPT Presentation

Citation preview

Page 1: What we will do today

What we will do today1. You’ll try to write a recursive function to solve a simple

problem2. We’ll return to the count number of “a”s example from the

previous day, and I’ll explore it a bit more3. I’ll discuss an alternative recursive string function4. I’ll discuss the “natural” recursive structure of files and

directories, and go through a example with that5. You will also write a recursive function with files and

directories6. If we have time: even more practice with recursive functions

Page 2: What we will do today

First Recursion Problem

• Go to http://codingbat.com/java/Recursion-1• Solve count7• If you finish, solve bunnyEars2• If you finish, do fibonacci (this one is so old

that I solved in my very first CS class…and it was pretty dang old then)

• If you finish, do a tiny green dance in your chair and then move on to some more

Page 3: What we will do today

public int countAs(String input) { if(input.isEmpty()) return 0; String restOfString = input.substring(1); int restOfStringCount = countAs(restOfString); if(input.charAt(0) == 'a') { return restOfStringCount + 1; } else { return restOfStringCount; } }

Page 4: What we will do today

A genuinely good example of recursion

How would you find the largest file within a directory (oh, and this directory can contain other directories)