Find the Difference

Posted 2020-10-06 白常福

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:
e

Explanation:
\'e\' is the letter that was added.

分析，找出多加上的单个字符。把s和t放到一起，则多余的一个一定是奇数个，可以用异或解决。

有问题是：

ch ^= t.charAt(i); 没有问题；

ch = ch^t.charAt(i);会报：

incompatible types: possible lossy conversion from int to char
待解决~~

参考：http://www.cnblogs.com/baichangfu/p/7468682.html

class Solution {
    public char findTheDifference(String s, String t) {
        t = s + t;
        char ch = 0;
        for(int i = 0; i < t.length(); i++){
            ch ^= t.charAt(i);
        }
        return ch;
    }
}