import sys



s = sys.stdin.readline().rstrip()



print((''.join([s[i] for i in range(len(s)) if i % 2 == 0])))

import sys



def main():

    s = sys.stdin.readline().rstrip()

    res = s[::2]

    print(res)



if __name__ == '__main__':

    main()
import sys

s = sys.stdin.readline().rstrip()
print(("".join([s[i] for i in range(len(s)) if i % 2 == 0])))

import sys


def main():
    s = sys.stdin.readline().rstrip()
    res = s[::2]
    print(res)


if __name__ == "__main__":
    main()

-s = sys.stdin.readline().rstrip() -print(("".join([s[i] for i in range(len(s)) if i % 2 == 0]))) + +def main(): +    s = sys.stdin.readline().rstrip() +    res = s[::2] +    print(res) + + +if __name__ == "__main__": +    main()