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 JAVA (judge verdict: WA: Presentation Error)

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO ?????????????????????????????????????????????
		Scanner kb=new Scanner(System.in);
		int x[]=new int[6000],y[]=new int[6000];
		x[0]=kb.nextInt();
		y[0]=kb.nextInt();
		int h=0;
		int i=0;
		while(x[h]!=0||y[h]!=0){
			h++;
			x[h]=kb.nextInt();
			y[h]=kb.nextInt();

		}

		while(x[i]!=0||y[i]!=0){
			if(x[i]>=y[i]){
				System.out.printf("%d %d",y[i],x[i]);
			}else if(x[i]<y[i]){
				System.out.printf("%d %d",x[i],y[i]);
			}
			System.out.println();
			i++;
		}
		System.out.println();
	}

}