leetcode--242-- Valid Anagram

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.

Follow up:
What if the inputs contain unicode characters? How would you adapt your solution to such case?

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