
# 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 math

N = int(eval(input()))

ans = math.factorial(N) % (10 ** 9 + 7)

print(ans)

# optimized version of the same code:

n = int(eval(input()))

from functools import reduce

print((reduce(lambda x,y:x*y%1000000007,list(range(1,n+1)))))
import math

N = int(eval(input()))
ans = math.factorial(N) % (10**9 + 7)
print(ans)

n = int(eval(input()))
from functools import reduce

print((reduce(lambda x, y: x * y % 1000000007, list(range(1, n + 1)))))

-import math +n = int(eval(input())) +from functools import reduce -N = int(eval(input())) -ans = math.factorial(N) % (10**9 + 7) -print(ans) +print((reduce(lambda x, y: x * y % 1000000007, list(range(1, n + 1)))))