#!/usr/bin/env python
# encoding: utf-8
"""

Created by Nick DeVeaux on 2014-08-07.

"""

import utils
import fileinput

def main():
    args = []
    for line in fileinput.input():
        args.append(line.rstrip())
    input = args[0]
    print(utils.reverse_dna(input))

if __name__ == '__main__':
	main()