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) {
    fscanf(STDIN, "%d %d", $a, $b);
    if ($a === 0 && $b === 0) {
        break;
    }else if ($a >= $b) {
        echo $b.' '.$a.PHP_EOL;
    }else{
        echo $a.' '.$b.PHP_EOL;
    }
}