
# 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()))

if x == 0:

  print((1))

else:

  print((0))

# optimized version of the same code:

x = int(eval(input()))

print((x^1))

x = int(eval(input()))
if x == 0:
    print((1))
else:
    print((0))

x = int(eval(input()))
print((x ^ 1))

-if x == 0: -    print((1)) -else: -    print((0)) +print((x ^ 1))