<# .SYNOPSIS Measures the speed of QuickSort .DESCRIPTION This PowerShell script measures the speed of the QuickSort algorithm. QuickSort is an in-place sorting algorithm. Developed by British computer scientist Tony Hoare in 1959 and published in 1961, it is still a commonly used algorithm for sorting. When implemented well, it can be somewhat faster than merge sort and about two or three times faster than heapsort. .PARAMETER numIntegers Specifies the number of integers to sort .EXAMPLE PS> ./measure-QuickSort.ps1 🧭 0.085 sec to sort 1000 integers by QuickSort .LINK https://github.com/fleschutz/PowerShell .NOTES Author: Markus Fleschutz | License: CC0 #> param([int]$numIntegers = 1000) class QuickSort { static Sort($targetList, $left, $right) { $i=$left $j=$right $pivot = $targetList[($left+$right)/2] while($i -le $j) { while($targetList[$i] -lt $pivot -and $i -lt $right) {$i++} while($targetList[$j] -gt $pivot -and $j -gt $left) {$j--} if($i -le $j) { $tmp = $targetList[$i] $targetList[$i]=$targetList[$j] $targetList[$j]=$tmp $i++ $j-- } } if($left -lt $j) {[QuickSort]::Sort($targetList, $left, $j)} if($i -lt $right) {[QuickSort]::Sort($targetList, $i, $right)} } } $list = (1..$numIntegers | foreach{Get-Random -minimum 1 -maximum $numIntegers}) $stopWatch = [system.diagnostics.stopwatch]::startNew() [QuickSort]::Sort($list, 0, $list.Count-1) [float]$elapsed = $stopWatch.Elapsed.TotalSeconds $elapsed3 = "{0:N3}" -f $elapsed # formatted to 3 decimal places "🧭 $elapsed3 sec to sort $numIntegers integers by QuickSort" exit 0 # success