input: Write a python function to count the number of differing characters in the same position of two strings.
  assert count_difference("Hello World", "Hello!") == 6
  assert count_difference("abcdef", "abcxyz") == 3
  assert count_difference("short", "longer") == 4
output: def count_difference(s1, s2):
      min_len = min(len(s1), len(s2))
      diff_count = sum(1 for i in range(min_len) if s1[i] != s2[i])
      diff_count += abs(len(s1) - len(s2))
      return diff_count