
# 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:

import numpy as np

N=int(eval(input()))

def gcd(a,b):

    c=int(np.floor(a/b))

    return a-b*c

if gcd(N,2)==0:

    print(N)

else:

    print((2*N))

# optimized version of the same code:

N=int(eval(input()))

if N%2==0:

    print(N)

else:

    print((2*N))
import numpy as np

N = int(eval(input()))


def gcd(a, b):
    c = int(np.floor(a / b))
    return a - b * c


if gcd(N, 2) == 0:
    print(N)
else:
    print((2 * N))

N = int(eval(input()))
if N % 2 == 0:
    print(N)
else:
    print((2 * N))

-import numpy as np - - - -def gcd(a, b): -    c = int(np.floor(a / b)) -    return a - b * c - - -if gcd(N, 2) == 0: +if N % 2 == 0: