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.

class Solution {
public:
    bool isAnagram(string
 
 s, string t) {
        if (s.size() != t.size()) return false;
        int m[26] = {0};
        for (int i = 0; i < s.size(); ++i) ++m[s[i] - 'a'];
        for (int i = 0; i < t.size(); ++i) {
            if (--m[t[i] - 'a'] < 0) return false;
        }
        return true;
    }
};