
# slower version:

s = input()
for i in range(len(s)):
  if i%2 == 0:
    print(s[i], end = '')


# optimized version of the same code:

s = input()
ans = ''
for i in range(len(s)):
  if i % 2 == 0:
    ans += s[i]
print(ans)



# slower version:

N=int(eval(input()))

a=list(map(int,input().split()))

for i in range(N):

  for j in range(1,31):

    if a[i]%(2**j)!=0:

      a[i]=j-1

      break

print((sum(a)))

# optimized version of the same code:

import sys

input = sys.stdin.buffer.readline



N = int(eval(input()))

A = list(map(int, input().split()))



def f(n):

  res = 0

  while n % 2 == 0:

    n //= 2

    res += 1

  return res



answer = 0

for a in A:

  answer += f(a)



print(answer)
N = int(eval(input()))
a = list(map(int, input().split()))
for i in range(N):
    for j in range(1, 31):
        if a[i] % (2**j) != 0:
            a[i] = j - 1
            break
print((sum(a)))

import sys

input = sys.stdin.buffer.readline
N = int(eval(input()))
A = list(map(int, input().split()))


def f(n):
    res = 0
    while n % 2 == 0:
        n //= 2
        res += 1
    return res


answer = 0
for a in A:
    answer += f(a)
print(answer)

+import sys + +input = sys.stdin.buffer.readline -a = list(map(int, input().split())) -for i in range(N): -    for j in range(1, 31): -        if a[i] % (2**j) != 0: -            a[i] = j - 1 -            break -print((sum(a))) +A = list(map(int, input().split())) + + +def f(n): +    res = 0 +    while n % 2 == 0: +        n //= 2 +        res += 1 +    return res + + +answer = 0 +for a in A: +    answer += f(a) +print(answer)