line = input()

count = len(line)

if count % 2 == 0:

  for i in range(0 ,count - 1 ,2):

    print(line[i],end ="")

else:

  for i in range(0 ,count ,2):

    print(line[i],end ="")

line = eval(input())

answer = line[::2]

print(answer)
line = input()
count = len(line)
if count % 2 == 0:
    for i in range(0, count - 1, 2):
        print(line[i], end="")
else:
    for i in range(0, count, 2):
        print(line[i], end="")

line = eval(input())
answer = line[::2]
print(answer)

-line = input() -count = len(line) -if count % 2 == 0: -    for i in range(0, count - 1, 2): -        print(line[i], end="") -else: -    for i in range(0, count, 2): -        print(line[i], end="") +line = eval(input()) +answer = line[::2] +print(answer)