
# 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()))

balls = np.array(list(map(int, input().split())))

time = 0

while np.all(balls % 2 == 0) and np.all(balls > 0):

    time += 1

    balls = balls / 2

print(time)

# optimized version of the same code:

import math

n = eval(input())

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

ans = float("inf")

for i in a:

    ans = min(ans, len(bin(i)) - bin(i).rfind("1") - 1)

print((round(ans)))
import numpy as np

n = int(eval(input()))
balls = np.array(list(map(int, input().split())))
time = 0
while np.all(balls % 2 == 0) and np.all(balls > 0):
    time += 1
    balls = balls / 2
print(time)

import math

n = eval(input())
a = list(map(int, input().split()))
ans = float("inf")
for i in a:
    ans = min(ans, len(bin(i)) - bin(i).rfind("1") - 1)
print((round(ans)))

-import numpy as np +import math -n = int(eval(input())) -balls = np.array(list(map(int, input().split()))) -time = 0 -while np.all(balls % 2 == 0) and np.all(balls > 0): -    time += 1 -    balls = balls / 2 -print(time) +n = eval(input()) +a = list(map(int, input().split())) +ans = float("inf") +for i in a: +    ans = min(ans, len(bin(i)) - bin(i).rfind("1") - 1) +print((round(ans)))