Problem:
Swapping Two Numbers

Write a program which reads two integers x and y, and prints them in ascending order.

Input

The input consists of multiple datasets. Each dataset consists of two integers x and y separated by a single space.

The input ends with two 0 (when both x and y are zero). Your program should not process for these terminal symbols.

Output

For each dataset, print x and y in ascending order in a line. Put a single space between x and y.

Constraints

0 ≤ x, y ≤ 10000

the number of datasets ≤ 3000

Sample Input

3 2
2 2
5 3
0 0

Sample Output

2 3
2 2
3 5

Solution in PHP (judge verdict: Accepted)

<?php

while (true) {
    list($num1, $num2) = explode(" ", trim(fgets(STDIN)));
    
    if ($num1 == "0" && $num2 == "0") {
        break;
    }
    
    if ($num1 > $num2) {
        echo $num2 . " " . $num1, PHP_EOL;
    } else {
        echo $num1 . " " . $num2, PHP_EOL;
    }
}