LeetCode 389. Find the Difference

389. Find the Difference

Description

Given two strings s and t which consist of only lowercase letters.
String t is generated by random shuffling string s and then add one more letter at a random position.
Find the letter that was added in t.

Example:Input:s = "abcd"t = "abcde"Output:eExplanation:'e' is the letter that was added.

Solution

• 题目意思就是给出两个全是小写字母组成的字符串，第二个字符串是第一个字符串打乱后再加一个新的字符组成的新字符串，让你找出这个新加的字符。
• 我的想法就是桶，将每个数组变成桶数组，统计每个字母出现的个数，在遍历，当某个数组的数值比另外一个多一个时就说明这是多出的字母，代码如下

class Solution {public:    int ss[26] = {0},tt[26] = {0};    char findTheDifference(string s, string t) {        int len = s.size();        for (int i = 0;i < len;i++) {            ss[s[i] - 'a']++;            tt[t[i] - 'a']++;        }        tt[t[len] - 'a']++;        for (int i = 0;i < 26;i++) {            if (tt[i] - ss[i] == 1)                return 'a' + i;        }        return 'a';//这是因为leetcode要求有返回值，所以任意返回一个，按照题目要求是不会运行到这行的。    }};