s = eval(input())

S =""

for i in range(0, len(s), 2):

  S += s[i]

print(S)
s = eval(input())

print((s[::2]))
s = eval(input())
S = ""
for i in range(0, len(s), 2):
    S += s[i]
print(S)

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

-S = "" -for i in range(0, len(s), 2): -    S += s[i] -print(S) +print((s[::2]))