String Rotate Right
This problem combines String
s, functions, and arrays. Super fun!
Write a function called rotateRight
that takes a String
as its first argument and a non-negative int
as
its second argument and rotates the String
by the given number of characters.
Here's what we mean by rotate:
CS125
rotated right by 1 becomes5CS12
CS125
rotated right by 2 becomes25CS1
CS125
rotated right by 3 becomes125CS
CS125
rotated right by 4 becomesS125C
CS125
rotated right by 5 becomesCS125
CS125
rotated right by 8 becomes125CS
And so on.
Notice how characters rotated off the right end of the String
wrap around to the left.
This problem is tricky! Here are a few hints:
- You will want to use the Java remainder operator to perform modular arithmetic, so please review the remainder operator.
- You will probably want to convert the
String
to an array of characters before you begin. - You can convert an array of characters
characters
back into aString
like this:new String(characters)
. - You can also solve this problem quite elegantly using
substring
.
If the passed String
argument is null
, you should return null
.
Good luck and have fun!