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Rotate String

Problem Statement​

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.

Leetcode Link

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.

Code​

Python
class Solution:
    def rotateString(self, s: str, goal: str) -> bool:
        if s == goal:
            return True

        s, goal = [*s], [*goal]

        # unpacking the strings (creates list)
        # ex: 'hello' -> ['h','e','l','l','o']


        for x in range(len(s)):
            a = s[0]
            s.pop(0); s.append(a)
            # rotate the string by saving the first character then removing it and then adding it to the end

            if s == goal:
                return True
            # checking if the rotated string is the same as the goal

        return False