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
$to_i = function($s){return (int)$s;};
for(;;) {
    $d = array_map($to_i, explode(" ", (fgets(STDIN))));
    if($d == array(0, 0)) break;
    sort($d);
    echo(implode(" ", $d));
    echo("\n");
}