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 Scala (judge verdict: Accepted)

import scala.io.StdIn.readLine

object Main extends App {

  val xs = {
    val lines = Iterator.continually(readLine())
    val xs    = for {
      line       <- lines
      Array(x, y) = line.split(" ").map { _.toInt }
    } yield (x, y)

    xs.takeWhile { _ != (0, 0) }
  }

  val results = xs.map {
    case (x, y) => if (x <= y) s"$x $y" else s"$y $x"
  }

  results.foreach(println)
}