#!/usr/bin/env python3

import sys

def inverted(i):
    if i == 0:
        return 1
    else:
        return 0

def filter(lis, pos, i):
    if len(lis) == 1:
        return lis
    if sum([b[pos] for b in lis]) >= sum([inverted(b[pos]) for b in lis]):
        val = i
    else:
        val = inverted(i)

    return [i for i in lis if i[pos] == val]

if __name__ == '__main__':
    lines = open(sys.argv[1]).readlines()
    
    bins = [[int(i) for i in list(l.strip('\n'))] for l in lines]

    # challenge 1
    lis = [0] * len(bins[0])

    for i in range(len(bins[0])):
        lis[i] = sum([b[i] for b in bins])
    
    g = ''
    e = ''

    for i in range(len(bins[0])):
        if lis[i] > 0.5 * len(lines):
            g += '1'
            e += '0'
        else:
            g += '0'
            e += '1'

    gamma = int(g, 2)
    eps = int(e,2)

    res1 = str(gamma * eps)
    print("challenge 1:" + res1 + "\n")

    ox = bins
    co2 = bins

    # challenge 2
    for i in range(len(bins[0])):
        ox = filter(ox, i, 1)
        co2 = filter(co2, i, 0)
    
    oxr = int(''.join(str(i) for i in ox[0]), 2)
    csr = int(''.join(str(i) for i in co2[0]), 2)

    res2 = str(oxr * csr)
    print("challenge 2:" + res2 + "\n")