s = list(eval(input()))

ans_list = []

for v in range(- (-len(s)//2)):

    ans_list.append(s[2 * v])

    

ans = "".join(ans_list)

print(ans)
s = list(eval(input()))

ans_list = [s[2 *i] for i in range(- (-len(s)//2))]

    

ans = "".join(ans_list)

print(ans)
s = list(eval(input()))
ans_list = []
for v in range(-(-len(s) // 2)):
    ans_list.append(s[2 * v])
ans = "".join(ans_list)
print(ans)

s = list(eval(input()))
ans_list = [s[2 * i] for i in range(-(-len(s) // 2))]
ans = "".join(ans_list)
print(ans)

-ans_list = [] -for v in range(-(-len(s) // 2)): -    ans_list.append(s[2 * v]) +ans_list = [s[2 * i] for i in range(-(-len(s) // 2))]