Created
May 16, 2012 20:36
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Counting Sort implemenatation
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#!/usr/bin/python | |
# -*- coding: utf-8 -*- | |
def countingSort(A, k): | |
""" | |
Implementation of counting sort. | |
@param A: the list of integers which should get sorted. | |
No element should be smaller than 1 | |
@param k: the highest number in A | |
""" | |
# Create empty list for the sorted list | |
B = [0 for el in A] | |
# Initialise counter with zeroes | |
C = [0 for el in xrange(0, k+1)] | |
# Count elements | |
for i in xrange(0, len(A)): | |
C[A[i]] += 1 | |
# How many elements are equal or lower? | |
for i in xrange(1, k + 1): | |
C[i] += C[i - 1] | |
# The actual sorting | |
for j in xrange(len(A)-1, 0 - 1, -1): | |
tmp = A[j] | |
tmp2= C[tmp] -1 | |
B[tmp2] = tmp | |
C[tmp] -= 1 | |
return B | |
""" Usage example """ | |
print countingSort([6,0,2,0,1,3,4,6,1,3,2], 6) |
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