import sys

S,T = input().split()



if not ( S.islower() and T.islower() ): sys.exit()

if not ( 1 <= len(S) <= 100 and 1 <= len(S) <= 100 ): sys.exit()



print(T,end='')

print(S)

import sys

S,T = input().split()



if not ( S.islower() and T.islower() ): sys.exit()

if not ( 1 <= len(S) <= 100 and 1 <= len(S) <= 100 ): sys.exit()



print(T,S,sep='')

import sys

S, T = input().split()
if not (S.islower() and T.islower()):
    sys.exit()
if not (1 <= len(S) <= 100 and 1 <= len(S) <= 100):
    sys.exit()
print(T, end="")
print(S)

import sys

S, T = input().split()
if not (S.islower() and T.islower()):
    sys.exit()
if not (1 <= len(S) <= 100 and 1 <= len(S) <= 100):
    sys.exit()
print(T, S, sep="")

-print(T, end="") -print(S) +print(T, S, sep="")