while(True):

 x,y=list(map(int,input().split()))

 if(x==0 and y==0):break

 if(x>y):

  tmp=x

  x=y

  y=tmp

 print(x,y)
while True:

 x,y=list(map(int,input().split()))

 if x==0 and y==0:break

 if x>y:

  tmp=x

  x=y

  y=tmp

 print(str(x)+" "+str(y))
while True:
    x, y = list(map(int, input().split()))
    if x == 0 and y == 0:
        break
    if x > y:
        tmp = x
        x = y
        y = tmp
    print(x, y)

while True:
    x, y = list(map(int, input().split()))
    if x == 0 and y == 0:
        break
    if x > y:
        tmp = x
        x = y
        y = tmp
    print(str(x) + " " + str(y))

-    print(x, y) +    print(str(x) + " " + str(y))