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.

def findTheDifference(s: String, t: String):Char = {
  var acc = t(t.length-1)
  for (i <- 0 until s.length) {
    acc ^= s(i) ^ t(i)
  }
  acc
}

findTheDifference("abcd", "abcde")