
# 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:

_,t=open(0);n=eval(t.replace(' ','|'));print((len(bin(n&-n))-3))

# optimized version of the same code:

n=eval([*open(0)][1].replace(*' |'))

print((len(bin(n&-n))-3))
_, t = open(0)
n = eval(t.replace(" ", "|"))
print((len(bin(n & -n)) - 3))

n = eval([*open(0)][1].replace(*" |"))
print((len(bin(n & -n)) - 3))

-_, t = open(0) -n = eval(t.replace(" ", "|")) +n = eval([*open(0)][1].replace(*" |"))