Skip to editor
File
New File Ctrl+N
New Folder

Save Ctrl+S
Upload File…
Download as ZIP

Delete File

Reset Files…
View
Toggle Sidebar Ctrl+B
Toggle Terminal Ctrl+`

Word Wrap Alt+Z

Exercise Info
Run
Run Code Ctrl+Enter
Save & Run F5

Clear Output
CS173: Intro to Computer Science - Recursion (3 pts)
Explorer
GitHub

Connect to GitHub to push and pull your project files to a repository.

On the page that opens, create a token with repo scope, copy it, then paste it below.

Paste the personal access token you created on GitHub with repo scope.

Click Refresh to load commit history
Exercise Info

Goals

  1. To implement a recursive function call

Instructions

Fill in the reverseString method below to recursively compute the string in reverse.

In this exercise [1], the main() method runs the code on “hello” and “stressed,” and they should give “olleh” and “desserts,” respectively (remember that when you’re feeling stressed during finals week!).

Hints

  • Since s.length()-1 is the last index of a string s, the last character of s can be extracted with s.charAt(s.length()-1)
  • Recall from chapter 2 that for a string s, s.substring(a, b) gives the substring of a string from index a to index b, not including b. So, for instance, if s = “stressed”, then s.substring(0, 7) would yield the string “stresse”. In this case, index 7 is the last index, but we don’t include that index.
  • If you get an error like too much recursion, this is the same as the stack overflow error we saw in the video. This probably means that the string you’re calling recursively isn’t actually decreasing in length, so you never reach the stopping condition of an empty string, and your code goes on forever. Check to make sure you’re taking the right substring in your recursive call.
  1. Developed by Prof. Chris Tralie ↩


The Ursinus-WebIDE by Chris Tralie (opens in new tab) and Bill Mongan (opens in new tab)

Your browser does not support WebGL. A graphical rendering canvas would appear here.


          
No suggestions. Code quality feedback will appear here.
Not logged in java
Ln 1, Col 1