#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
from ipoperate import ip2long, long2ip, ips2range
 
if len(sys.argv) == 1:
    f = sys.stdin
else:
    f = open(sys.argv[1]) 

ips = [line.strip('\n') for line in f.readlines()]

ip_list = sorted([ int(ip2long(j)) for j in ips])
ip_ranges = ips2range([long2ip(k) for k in ip_list])
for ip_range in ip_ranges:
    print '-'.join(ip_range)
