Rotate String

Problem

Given two strings s and goal, return true if and only if s can become goal after some number of shifts on s.

A shift on s consists of moving the leftmost character of s to the rightmost position.

  • For example, if s = “abcde”, then it will be “bcdea” after one shift.

Example 1:

Input: s = "abcde", goal = "cdeab"
Output: true

Example 2:

Input: s = "abcde", goal = "abced"
Output: false

Constraints:

  • 1 <= s.length, goal.length <= 100
  • s and goal consist of lowercase English letters.

Solution

class Solution {
    public boolean rotateString(String s, String goal) {
        return (s + s).contains(goal);
    }
}

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