(Easy) Rotate String- LeetCode

Description:

We are given two strings, A and B.

A shift on A consists of taking string A and moving the leftmost character to the rightmost position. For example, if A = 'abcde', then it will be 'bcdea' after one shift on A. Return Trueif and only if A can become B after some number of shifts on A.

Example 1:
Input: A = 'abcde', B = 'cdeab'
Output: true

Example 2:
Input: A = 'abcde', B = 'abced'
Output: false

Note:

• A and B will have length at most 100.

Accepted

45,394

Submissions

92,198

 

Solution:

class Solution {
    public boolean rotateString(String A, String B) {
        
        if((A==null&&B==null) ||(A.length()==0&&B.length()==0)){
            return true;
        }
        
        else if( A==null||B==null){
            return false;
            
        }
        else{
                   for(int i =1; i<=A.length();i++)
            {
                if(B.equals(Shift(A,i))){
                       return true;
                }

            }
        }
     
        
        return false;
    }
    
    public String Shift(String s, int a){
        
        String res = s.substring(a);
        
        res= res+ s.substring(0,a);
        
        return res;
    }
}