# -*- coding: UTF-8 -*-
import sys
import base64


if __name__ == "__main__":
    if len(sys.argv) != 3 : 
        print("error")
    else :
        print( "{}{}{}".format( base64.b64decode( sys.argv[1] ) , base64.b64decode( sys.argv[2] ) , '\x0A\x01' ))