
# 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:

n = int(eval(input()))

r = int(n**.5)

for i in range(r):

  if n % (r-i) == 0:

    print(( (r-i) + n//(r-i) - 2 ))

    break

# optimized version of the same code:

n = int(eval(input()))

s = int(n**.5)

for i in range(s):

  if n % (s-i) == 0:

    print(((s-i) + n // (s-i) - 2))

    break
n = int(eval(input()))
r = int(n**0.5)
for i in range(r):
    if n % (r - i) == 0:
        print(((r - i) + n // (r - i) - 2))
        break

n = int(eval(input()))
s = int(n**0.5)
for i in range(s):
    if n % (s - i) == 0:
        print(((s - i) + n // (s - i) - 2))
        break

-r = int(n**0.5) -for i in range(r): -    if n % (r - i) == 0: -        print(((r - i) + n // (r - i) - 2)) +s = int(n**0.5) +for i in range(s): +    if n % (s - i) == 0: +        print(((s - i) + n // (s - i) - 2))