#!/usr/bin/env python3

import sys


if __name__ == '__main__':
    lines = open(sys.argv[1]).read().strip('\n\n').split('\n') # or split \n\n or sth similar
    nums = [int(i) for i in lines]

    # challenge 1
    res1 = ""
    print("challenge 1:" + res1 + "\n")

    # challenge 2
    res2 = ""
    print("challenge 2:" + res2 + "\n")