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Bucket Sort

Bucket Sort
# This program will illustrate how to implement bucket sort algorithm
# Wikipedia says: Bucket sort, or bin sort, is a sorting algorithm that works by distributing the
# elements of an array into a number of buckets. Each bucket is then sorted individually, either using
# a different sorting algorithm, or by recursively applying the bucket sorting algorithm. It is a
# distribution sort, and is a cousin of radix sort in the most to least significant digit flavour.
# Bucket sort is a generalization of pigeonhole sort. Bucket sort can be implemented with comparisons
# and therefore can also be considered a comparison sort algorithm. The computational complexity estimates
# involve the number of buckets.
# Time Complexity of Solution:
# Best Case O(n); Average Case O(n); Worst Case O(n)
from __future__ import print_function
from insertion_sort import insertion_sort
import math
DEFAULT_BUCKET_SIZE = 5
def bucketSort(myList, bucketSize=DEFAULT_BUCKET_SIZE):
if(len(myList) == 0):
print('You don\'t have any elements in array!')
minValue = myList[0]
maxValue = myList[0]
# For finding minimum and maximum values
for i in range(0, len(myList)):
if myList[i] < minValue:
minValue = myList[i]
elif myList[i] > maxValue:
maxValue = myList[i]
# Initialize buckets
bucketCount = math.floor((maxValue - minValue) / bucketSize) + 1
buckets = []
for i in range(0, bucketCount):
buckets.append([])
# For putting values in buckets
for i in range(0, len(myList)):
buckets[math.floor((myList[i] - minValue) / bucketSize)].append(myList[i])
# Sort buckets and place back into input array
sortedArray = []
for i in range(0, len(buckets)):
insertion_sort(buckets[i])
for j in range(0, len(buckets[i])):
sortedArray.append(buckets[i][j])
return sortedArray
if __name__ == '__main__':
sortedArray = bucketSort([12, 23, 4, 5, 3, 2, 12, 81, 56, 95])
print(sortedArray)
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