while 1:

 a=eval(input())

 if a=='0 0':break

 print((*sorted(map(int,a.split()))))
import sys

for s in sys.stdin:

 if'0 0\n'==s:break

 print((*sorted(map(int,s.split()))))
while 1:
    a = eval(input())
    if a == "0 0":
        break
    print((*sorted(map(int, a.split()))))

import sys

for s in sys.stdin:
    if "0 0\n" == s:
        break
    print((*sorted(map(int, s.split()))))

-while 1: -    a = eval(input()) -    if a == "0 0": +import sys + +for s in sys.stdin: +    if "0 0\n" == s: -    print((*sorted(map(int, a.split())))) +    print((*sorted(map(int, s.split()))))