LeetCode - 389. Find the Difference

Given two strings s and t which consist of only lowercase letters.

String t is generated by random shuffling string s and then add one more letter at a random position.

Find the letter that was added in t.

Example:

Input:
s = "abcd"
t = "abcde"

Output:
e

Explanation:
'e' is the letter that was added.

public class Solution {
public char findTheDifference(String s, String t) {
int[] sarr = new int[26];
int[] tarr = new int[26];
Arrays.fill(sarr, 0);
Arrays.fill(tarr, 0);
for (int i=0; i<s.length(); i++) {
char ch = s.charAt(i);
sarr[ch-'a'] ++;
}
for (int i=0; i<t.length(); i++) {
char ch = t.charAt(i);
tarr[ch-'a'] ++;
}
for (int i=0; i<26; i++) {
if (tarr[i] != sarr[i]) {
return (char)(i+(int)'a');
}
}
return 'a';
}
}