s = str(eval(input()))

ans = []

for i in range(len(s)):

    if i%2 == 0:

        ans.append(s[i])

print((''.join(ans)))

s = str(eval(input()))

n = len(s)

ans = []

for i in range(n):

    if i%2 == 0:

        ans.append(s[i])

print((''.join(ans)))

s = str(eval(input()))
ans = []
for i in range(len(s)):
    if i % 2 == 0:
        ans.append(s[i])
print(("".join(ans)))

s = str(eval(input()))
n = len(s)
ans = []
for i in range(n):
    if i % 2 == 0:
        ans.append(s[i])
print(("".join(ans)))

+n = len(s) -for i in range(len(s)): +for i in range(n):