Problem:
Toggling Cases

Write a program which converts uppercase/lowercase letters to lowercase/uppercase for a given string.

Input

A string is given in a line.

Output

Print the converted string in a line. Note that you do not need to convert any characters other than alphabetical letters.

Constraints

The length of the input string < 1200

Sample Input

fAIR, LATER, OCCASIONALLY CLOUDY.

Sample Output

Fair, later, occasionally cloudy.

Solution in PHP (judge verdict: Accepted)

<?php
$s = str_split(trim(fgets(STDIN)));
foreach ($s as $c) {
  if (ctype_upper($c)) echo strtolower($c);
  else if (ctype_lower($c)) echo strtoupper($c);
  else echo $c;
}
echo "\n";