LeetCode_389. Find the Difference

389. Find the Difference

Easy

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.

package leetcode.easy;

public class FindTheDifference {
	public char findTheDifference(String s, String t) {
		char[] first = s.toCharArray();
		char[] second = t.toCharArray();
		int res = 0;
		for (int i = 0; i < first.length; i++) {
			res += second[i];
			res -= first[i];
		}
		res += second[second.length - 1];
		return (char) res;
	}

	@org.junit.Test
	public void test() {
		System.out.println(findTheDifference("abcd", "abcde"));
	}
}