
# 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()))

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



counter = 0

while True:

    if np.sum(a_list % 2) > 0:

        break

    counter += 1

    a_list = a_list / 2

print(counter)


# optimized version of the same code:

n = int(eval(input()))

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



status = True

execute = 0

while status:

    for i in range(n):

        if a_list[i] % 2 == 1:

            status = False

            break

        else:

            a_list[i] = a_list[i] / 2

    if status:

        execute += 1

print(execute)

import numpy as np

n = int(eval(input()))
a_list = np.array(list(map(int, input().split())))
counter = 0
while True:
    if np.sum(a_list % 2) > 0:
        break
    counter += 1
    a_list = a_list / 2
print(counter)

n = int(eval(input()))
a_list = list(map(int, input().split()))
status = True
execute = 0
while status:
    for i in range(n):
        if a_list[i] % 2 == 1:
            status = False
            break
        else:
            a_list[i] = a_list[i] / 2
    if status:
        execute += 1
print(execute)

-import numpy as np - -a_list = np.array(list(map(int, input().split()))) -counter = 0 -while True: -    if np.sum(a_list % 2) > 0: -        break -    counter += 1 -    a_list = a_list / 2 -print(counter) +a_list = list(map(int, input().split())) +status = True +execute = 0 +while status: +    for i in range(n): +        if a_list[i] % 2 == 1: +            status = False +            break +        else: +            a_list[i] = a_list[i] / 2 +    if status: +        execute += 1 +print(execute)