RotateString.js

// Source : https://leetcode.com/problems/rotate-string
// Author : Dean Shi
// Date   : 2018-03-27

/***************************************************************************************
 * 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 True if 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.
 ***************************************************************************************/

/**
 * @param {string} A
 * @param {string} B
 * @return {boolean}
 */
var rotateString = function(A, B) {
    return A.length === B.length && (A + A).includes(B)
};