[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?

Thought process:
Iterate through both strings, count the number of each character, and compare the counts.

Solution:

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class Solution {
    public boolean isAnagram(String s, String t) {
        int[] count = new int[26];
        for (char c : s.toCharArray()) {
            count[c - 'a']++;
        }
        for (char c : t.toCharArray()) {
            count[c - 'a']--;
        }
        
        for (int i : count) {
            if (i != 0) {
                return false;
            }
        }
        return true;
    }
}

Time complexity: O(s + t).

Follow-up: initialize count array to have a length of 256.
Location: Philadelphia, PA, USA

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