import java.io.*;

class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		while(true){
			String[] a=br.readLine().split(" ");
			if(a[0].equals("0")&&a[1].equals("0")) break;
	        int x=Integer.parseInt(a[0]);
	        int y=Integer.parseInt(a[1]);
	        if(x>y){
	        	sb.append(y+" "+x+"\n");
	        }else{
	        	sb.append(x+" "+y+"\n");
	        }
		}
		System.out.print(sb);
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz