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: Accepted)

import java.util.Scanner;
import java.util.ArrayList;

public class Main{

	public static void main(String[] args) {

		//
		ArrayList<Integer> big_list = new ArrayList<Integer>();
		ArrayList<Integer> small_list = new ArrayList<Integer>();
		
		int big = 0;
		int small = 0;

		// テキスト入力
		Scanner sc = new Scanner(System.in);
		
		while(true){
			// 入力文字を取得
			int first = sc.nextInt();
			int second = sc.nextInt();
			
			//
			if(first==0 && second==0){
				break;
			}

			// 小さい順に並べる
			if (first >= second) {
				//
				big = first;
				small = second;
			} else {
				big = second;
				small = first;
			}
			
			//リストに入れる
			big_list.add(big);
			small_list.add(small);
		}

		//ループ
		for(int i = 0;i < big_list.size();i++)
		// 出力
				System.out.println(small_list.get(i)+ " " + big_list.get(i));
	}
}