面试题 01.09

Given two strings, s1 and s2, write code to check if s2 is a rotation of s1 (e.g.,"waterbottle" is a rotation of"erbottlewat"). Can you use only one call to the method that checks if one word is a substring of another?

Example 1:

Input: s1 = "waterbottle", s2 = "erbottlewat" Output: True Example 2:

Input: s1 = "aa", "aba" Output: False

Note:

0 <= s1.length, s1.length <= 100000

Solutions

class Solution {
public:
    bool isFlipedString(string s1, string s2) {
        return s1.size() == s2.size() && (s1 + s1).find(s2) != string::npos;
    }
};