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
$a = str_split(trim(fgets(STDIN)));

    for($i=0;$i<=(count($a)-1);$i++){
        if(ctype_upper($a[$i])){
            echo strtolower($a[$i]);
        }elseif(ctype_lower($a[$i])){
            echo strtoupper($a[$i]);
        }else{
            echo $a[$i];
        }
    }
    echo PHP_EOL;