Leetcode Everyday: 242. Valid Anagram

https://leetcode.com/problems/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?

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