#!/usr/bin/env python

import grp
import pwd
import sys

def usage():
    print >> sys.stderr, "Usage: unknown-owners (--user | --group)"

if len(sys.argv) != 2:
    usage()
    sys.exit(1)

if sys.argv[1] == '--user':
    max_name_len = max([len(x.pw_name) for x in pwd.getpwall()])
elif sys.argv[1] == '--group':
    max_name_len = max([len(x.gr_name) for x in grp.getgrall()])
else:
    usage()
    sys.exit(1)

print 'x' * (max_name_len + 1)