PowerShellで実装してみるサーチアルゴリズム(リニアサーチ、バイナリサーチ）

# search function
function linearSearch([array]$data, [int]$target){

    for($i = 0; $i -lt $data.Length; $i++){
    
        if($data[$i] -eq $target){
            return $i
        }
    }
    
    return -1
}

#position= (0, 1, 2, 3, 4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,  15)
$array1 = @(0, 1, 2, 4, 5, 15, 23, 26, 30, 31, 33, 35, 50, 75, 99, 100)

Write-Host("配列：" + $array1)

$target = 26
Write-Host("検索値：" + $target)

$result = linearSearch $array1 $target
Write-Host ("結果：" + $result)

Read-Host

# search function
function binarySearch([array]$data, [int]$target){

    $head = 0
    $tail = $data.Length -1

    while($head -le $tail){
        $middle = [Math]::Floor( ($head + $tail) / 2 )
        
        if($data[$middle] -eq $target){
            # 位置検出、終了
            return $middle
        }

        # 検索位置の変更
        if($data[$middle] -lt $target){
            $head = $middle + 1
        }else{
            $tail = $middle - 1
        }

    }
    return -1
}

#position= (0, 1, 2, 3, 4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,  15)
$array1 = @(0, 1, 2, 4, 5, 15, 23, 26, 30, 31, 33, 35, 50, 75, 99, 100)

Write-Host("配列：" + $array1)

$target = 15
Write-Host("検索値：" + $target)

$result = binarySearch $array1 $target
Write-Host ("結果：" + $result)

Read-Host