#!/bin/python
import ipaddress
import sys
import argparse

parser = argparse.ArgumentParser()
parser.add_argument('-t', '--test', action='store_const', const=True, help='Тестовый режим')
parser.add_argument('-s', '--summask', type=int, help='Суммаризация по маске')
args = parser.parse_args()

def read_ips():
    ip_cnt,prefixes = 0, {}
    for line in sys.stdin:
        line, ip_cnt = line.strip('\n'), ip_cnt + 1
        try:
            if ipaddress.ip_network(line) or ipaddress.ip_address(line):
                prefix = ipaddress.ip_network(line).network_address.compressed
                prefixlen = ipaddress.ip_network(line).prefixlen
                if args.summask and prefixlen > args.summask:
                    supernet = ipaddress.ip_network(prefix,prefixlen).supernet(new_prefix=args.summask)
                    prefix = supernet.network_address.compressed
                    prefixlen = supernet.prefixlen
                prefixes[prefix] = prefixlen
        except ValueError:
            continue #bad subnet address
    if args.test:
        print('{} IP/Net -> stdin'.format(ip_cnt))
    return prefixes


def subnets_join(prefixes, new_prefixlen):
    new_prefixes = {}
    for network_address, prefixlen in prefixes.items():
        if prefixlen == new_prefixlen + 1:
            supernet = ipaddress.ip_network(network_address, prefixlen).supernet(new_prefix=new_prefixlen)
            new_network_address = supernet.network_address.compressed
            subnets = list(supernet.subnets())
            prefix_count = 0
            for subnet in subnets:
                if prefixes.get(subnet.network_address.compressed) == subnet.prefixlen:
                    prefix_count += 1
            if prefix_count > 1:
                new_prefixes[new_network_address] = new_prefixlen
            else:
                new_prefixes[network_address] = prefixlen
        else:
            new_prefixes[network_address] = prefixlen
    return new_prefixes


prefixes = read_ips()
maxprefixlen,start_cnt = 32, len(prefixes)
for prefixlen in range(maxprefixlen, 0, -1):
    prefixes = subnets_join(prefixes, prefixlen)
    if args.test:
        print('/{} - {} - {}%'.format(prefixlen, len(prefixes), int(100 / start_cnt * len(prefixes))))
if not args.test:
    [print('{}/{}'.format(pref, preflen)) for pref, preflen in prefixes.items()]