import java.util.Scanner;
class Main{
public static void main(String[] args){
Scanner scan=new Scanner(System.in);
while(true){
String A=scan.next();
String B=scan.next();
int a=Integer.parseInt(A);
int b=Integer.parseInt(B);
if(a==0&&b==0)
	break;
int okiba;
if(a>b){
okiba=a;
a=b;
b=okiba;
}
System.out.println(a+" "+b);
}
}
}
/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