Quick Sort in Powershell

Welcome to the Quick Sort in Powershell page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

function Show-Usage() {
    Write-Host 'Usage: please provide a list of at least two integers to sort in the format "1, 2, 3, 4, 5"'
    Exit 1
}

function Parse-IntList([string]$Str) {
    @($Str.Split(",") | ForEach-Object { [int]::Parse($_) })
}

# Source: https://en.wikipedia.org/wiki/Quicksort#Lomuto_partition_scheme
function Invoke-QuickSort([array]$Values) {
    Invoke-QuickSortRec $Values 0 ($Values.Length - 1)
}

function Invoke-QuickSortRec([array]$Values, [int]$Lo, [int]$Hi) {
    if ($Lo -ge 0 -and $Lo -le $Hi) {
        # Partition array and get pivot value
        $p = Invoke-Partition $Values $Lo $Hi

        # Sort left side of partition
        Invoke-QuickSortRec $Values $Lo ($p - 1)

        # Sort right side of partition
        Invoke-QuickSortRec $Values ($p + 1) $Hi
    }
}

function Invoke-Partition([array]$Values, [int]$Lo, [int]$Hi) {
    # Choose the last element as the pivot
    $pivot = $Values[$Hi]

    # Temporary pivot index
    $i = $Lo

    for ($j = $Lo; $j -le ($Hi - 1); $j++) {
        # If the current element is less than or equal to the pivot,
        if ($Values[$j] -le $pivot) {
            # Swap the current element with the element at the temporary pivot index
            $Values[$i], $Values[$j] = $Values[$j], $Values[$i]

            # Move the temporary pivot index forward
            $i++
        }
    }

    # Swap the pivot with the last element
    $Values[$i], $Values[$Hi] = $Values[$Hi], $Values[$i]

    # Return pivot index
    $i
}

if ($args.Length -lt 1 -or -not $args[0]) {
    Show-Usage
}

try {
    $values = Parse-IntList $args[0]
    if ($values.Length -lt 2) {
        Show-Usage
    }
} catch {
    Show-Usage
}

Invoke-QuickSort $values
Write-Output ($values -join ', ')

Quick Sort in Powershell was written by:

• rzuckerm

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

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