242 Valid Anagram

Description:

Given two strings s and t, write a function to determine if t is an anagram of s.

For example,
s = "anagram", t = "nagaram", return true.
s = "rat", t = "car", return false.

Note:
You may assume the string contains only lowercase alphabets.

实现代码如下：

class Solution {
public:
    bool isAnagram(string s, string t) {
        unordered_map<char, int> map1;
        if(s.length() != t.length()) return false;
        for(int i = 0; i < s.length(); i++) {
            map1[s[i]]++;
        }
        for(int i = 0; i < t.length(); i++) {
            map1[t[i]]--;
        }
        for(auto it = map1.begin(); it!= map1.end(); it++) {
            if((*it).second != 0) {
                return false;
            }
        }
        return true;
    }
};