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
$o=array();
while(1){
  $x=explode(' ',trim(fgets(STDIN)));
  if($x[0]||$x[1]) $o[]=($x[0]<$x[1])?$x[0].' '.$x[1]:$x[1].' '.$x[0];
  else break;
}
print implode(PHP_EOL,$o);
?>