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?

题目含义：判断给定两个字符串是否为相同字母不同排列的单词

    public boolean isAnagram(String s, String t) {
        if (s.length() != t.length()) return false;
        int[] letter=new int[26];
        for (int i=0;i<s.length();i++)
        {
            letter[s.charAt(i) - 'a']++;
        }
        for (int i=0;i<t.length();i++)
        {
            if ((--letter[t.charAt(i)-'a'])<0) return false;
        }
        return true;        
    }