#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
int main()
{
	int n, x;
	int arr[1000][3] = { 0 };
	scanf("%d", &n);
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < 2; j++)
		{
			scanf("%d", &x);
			arr[i][j] = x;
		}
	}
	for (int i = 0; i < n; i++)
	{
		
			if (arr[i][0] == arr[i][1])
				printf("%d\n", arr[i][0]);
			else if (arr[i][0] > arr[i][1])
				printf("%d %d\n", arr[i][1], arr[i][0]);
			else
				printf("%d %d\n", arr[i][0], arr[i][1]);
		
	}
	return 0;
}