s = list(eval(input()))

print((''.join(s[::2])))
s = eval(input())

print((s[0::2]))
s = list(eval(input()))
print(("".join(s[::2])))

s = eval(input())
print((s[0::2]))

-s = list(eval(input())) -print(("".join(s[::2]))) +s = eval(input()) +print((s[0::2]))