Sorting Algorithm Tutorials - Herong's Tutorial Examples - 6.12, by Herong Yang
Bubble Sort - Implementation in Perl
This section provides a tutorial on how to implement the Bubble Sort algorithm in Perl.
Bubble Sort is a simple and slow sorting algorithm that repeatedly steps through the collection, compares each pair of adjacent elements and swaps them if they are in the wrong order.
The basic idea of Bubble Sort algorithm can be described as these steps:
1. Data elements are grouped into two sections: a sorted section and an un-sorted section.
2. Go through every element in the un-sorted section and re-arrange its position with its neighbor to put the element with higher order on the higher position. At the end, the element with the highest order will be on top of the un-sorted section, and moved to the bottom of the sorted section.
3. Repeat step 2 until no more elements left in the un-sorted section.
In the sorting algorithm, if you watch the move of the elements with higher orders, they are like bubbles in the water, floating slowly from the bottom to the top.
Here is my Perl implementation of Bubble Sort algorithm:
#- Sort_Function.pl #- Copyright (c) 2015 HerongYang.com. All Rights Reserved. #- sub bubbleSort { my ($a, $fromIndex, $toIndex) = @_; for ($i=$toIndex-1; $i>$fromIndex; $i--) { $isSorted = 1; for ($j=$fromIndex; $j<$i; $j++) { if (($a->[$j])>$a->[$j+1]) { $isSorted = 0; $d = $a->[$j+1]; $a->[$j+1] = $a->[$j]; $a->[$j] = $d; } } last if ($isSorted); } } # Functions for other sorting algorithms ... #- End 1;
The following diagram illustrates how this implementation works:
--17 42 53 67 ... 92 | | | | | +---+---+---------------+---+---+---+---+---+---------------+ | | | / 29 36 11 ... 24 39 | | | | fromIndex j i toIndex-1
Note that:
Here are the performance test results of bubbleSort() function using Perl 5.18. The execution of bubbleSort() is so slow. I have to reduce the number of tests to 10 and 1 to avoid long waiting time.
Array size: 10000 Average sorting time: 19343.8862792969 milliseconds Number of tests: 10 Performance: 1934.38862792969 O(N) microseconds Performance: 145.577250069532 O(N*Log2(N)) microseconds Performance: 0.193438862792969 O(N*N) microseconds Array size: 20000 Average sorting time: 78359.980859375 milliseconds Number of tests: 10 Performance: 3917.99904296875 O(N) microseconds Performance: 274.221578576619 O(N*Log2(N)) microseconds Performance: 0.195899952148438 O(N*N) microseconds Array size: 30000 Average sorting time: 177352.602050781 milliseconds Number of tests: 1 Performance: 5911.75340169271 O(N) microseconds Performance: 397.490932147987 O(N*Log2(N)) microseconds Performance: 0.19705844672309 O(N*N) microseconds
Here is the comparison of bubbleSort() performance with other sorting functions. As you can see, Bubble Sort is much slower than other sorting functions.
Array Size 10000 20000 30000 100000 200000 300000 ---------- ----- ----- ----- ------ ------ ------ JDK Arrays.sort 25 66 112 PHP sort() 3 7 13 75 Perl sort() 11 22 36 171 Insertion Sort 4125 16015 37098 Selection Sort 8054 31249 68985 Bubble Sort 19344 78360 177353
Table of Contents
Introduction of Sorting Algorithms
Java API for Sorting Algorithms
Insertion Sort Algorithm and Java Implementation
Selection Sort Algorithm and Java Implementation
Bubble Sort Algorithm and Java Implementation
Quicksort Algorithm and Java Implementation
Merge Sort Algorithm and Java Implementation
Heap Sort Algorithm and Java Implementation
Shell Sort Algorithm and Java Implementation
Sorting Algorithms Implementations in PHP
►Sorting Algorithms Implementations in Perl
Sort_Test.pl - Sorting Performance Test
Insertion Sort - Implementation in Perl
Selection Sort - Implementation in Perl
►Bubble Sort - Implementation in Perl
Quicksort - Implementation in Perl
Merge Sort - Implementation in Perl
Heap Sort - Implementation in Perl
Shell Sort - Implementation in Perl
Sorting Algorithms Implementations in Python