"""
Bucketsort implementation using linked lists

Copyright 2020, University of Freiburg.

Philipp Schneider <philipp.schneider@cs.uni-freiburg.de>
"""

import random
import time
from Queue import Queue  # noqa

from ListElement import ListElement  # noqa


def bucket_sort(array, k, key=lambda x: x):
    '''
    Implements the bucket sort algorithm to sort
        data elements using a key function to
        assign sorting keys to data elements

    Args:
        array: array of data elements
        k: largest key
        key: a function mapping data elements to values
        in range(k+1) (idendity function as default)

    >>> array = [10-i for i in range(10)]
    >>> bucket_sort(array, 10)
    >>> str(array)
    '[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]'
    '''


def bucket_sort_performance():
    '''
    Method that outputs key range and elapsed time for sorting.
    '''
    for k in range(2*10**4, (12*(10**5))+1, 2*10**4):
        array = [random.randint(0, k) for i in range(10**4)]
        start_time = time.time()
        bucket_sort(array, k)
        run_time = (time.time() - start_time) * 1000
        print("%d\t%.1f" % (k, run_time))


if __name__ == "__main__":
    bucket_sort_performance()