LeetCode（389） Find the Difference

题目

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.

分析

很简单的一道题目，两个字符串只有一个字符不同，用一个哈希表即可解决。

代码

class Solution {
public:
	char findTheDifference(string s, string t) {
		int sL = s.length(), tL = t.length();

		vector<int> v(256, 0);
		for (int i = 0; i < sL; ++i)
			++v[s[i]];

		for (int i = 0; i < tL; ++i)
		{
			--v[t[i]];
			if (v[t[i]] < 0)
				return t[i];
		}//for
		return ' ';
	}

};