#!/usr/bin/env python3

"""Strip off the first n components of a list of pathnames on stdin."""

import os
import sys


def usage(retval):
    """Output a usage message and exit."""
    if retval == 0:
        file_ = sys.stdout
    else:
        file_ = sys.stderr

    print(f'Usage: {sys.argv[0]} --count n', file=file_)
    print('Reads paths from stdin, one path per line, and strips off count directories on the left.', file=file_)

    sys.exit(retval)


def main():
    """Start the ball rolling."""
    count = None
    while sys.argv[1:]:
        if sys.argv[1] == '--count':
            count = int(sys.argv[2])
            del sys.argv[1]
        elif sys.argv[1] in ('-h', '--help'):
            usage(0)
        else:
            print(f'{sys.argv[0]}: Unrecognized option: {sys.argv[1]}', file=sys.stderr)
            usage(1)
        del sys.argv[1]

    if count is None:
        print(f'{sys.argv[0]}: --count is a required option', file=sys.stderr)
        usage(1)

    too_short_count = 0

    for line_sans_newline in (line.lstrip("/").rstrip("\n") for line in sys.stdin):
        fields = line_sans_newline.split(os.path.sep)
        if len(fields) <= count:
            too_short_count += 1
            continue
        keep_fields = fields[count:]
        result = os.path.join(*keep_fields)
        print(result)

    if too_short_count not in (0, 1):
        sys.stderr.write('Got {} too-short lines'.format(too_short_count))
        sys.exit(1)


main()