
# 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:

x=int(eval(input()))

for i in range(-118,120):

  for j in range(-119,129):

    if i**5-j**5==x:

      print((i,j))

      exit()

# optimized version of the same code:

x = int(eval(input()))

for i in range(120):

  for j in range(-119,129):

    if i**5 - j**5 == x:

      print((i, j))

      exit()
x = int(eval(input()))
for i in range(-118, 120):
    for j in range(-119, 129):
        if i**5 - j**5 == x:
            print((i, j))
            exit()

x = int(eval(input()))
for i in range(120):
    for j in range(-119, 129):
        if i**5 - j**5 == x:
            print((i, j))
            exit()

-for i in range(-118, 120): +for i in range(120):