function f($str,$n){if($n -eq 1){foreach($i in $str){$i}}else{foreach($j in (f -str $str -n ($n-1))){foreach($k in $str){$j+$k}}}}
$str="123abc".TocharArray()
$n=6
1..$n|%{f -str $str -n $_}>111.txt
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function f($str,$n)
{
	[System.Collections.ArrayList]$a=@()
	[System.Collections.ArrayList]$b=@()
	if($n -eq 1)
	{
		foreach($i in $str)
		{
			$c=$a.Add($i)
		}
		$c=$b.Add($a)
		return $b
	}
	else
	{
		$c=$b.Add($str)
		for($m=0;$m -lt $n-1;$m++)
		{
			foreach($j in $b[$m])
			{
				foreach($k in $str)
				{
					$c=$a.Add($j+$k)
				}			
			}
			$c=$b.Add($a)
			$a=@()
		}	
		return $b
	}
}
$str="abc123".TocharArray()
$n=1
(f -str $str -n $n)>result.txt
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$a = [System.Collections.Stack]::new()
function cr($n, $s, $a) {if($a.count -eq $n){return $a.toarray() -join ''}for($i=0;$i -lt $s.length;$i++){$a.push($s[$i]);cr $n $s $a;$a.pop()|out-null}}
1..3 | %{$a.clear();cr $_ "asdfg" $a}
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function combr(n, s, i) {
    if (length(s)==n) {
        print s
        return
    }
    for (i=1;i<=length($0);i++) {
        s = s substr($0, i, 1)
        combr(n, s)
        s = substr(s, 1, length(s) - 1)
    }
}
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$ranGen = New-Object System.Random
$RepeatCount = 10000

'Wrapped in a function = {0}ms' -f (Measure-Command -Expression {
    function Get-RandNum_Core {
        param ($ranGen)
        $ranGen.Next()
    }

    for ($i = 0; $i -lt $RepeatCount; $i++) {
        $Null = Get-RandNum_Core $ranGen
    }
}).TotalMilliseconds

'For-loop in a function = {0}ms' -f (Measure-Command -Expression {
    function Get-RandNum_All {
        param ($ranGen)
        for ($i = 0; $i -lt $RepeatCount; $i++) {
            $Null = $ranGen.Next()
        }
    }

    Get-RandNum_All $ranGen
}).TotalMilliseconds
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