SGMJQF*ck interpreter by x0wl

$code = $args[0] #quine: <s>g.[<+>[-]j][-]+++++++++++++.q

if($code -eq $null){break}

$code = $code.ToCharArray()

$meptr = 0
$rwptr = 0
$exptr = 0
$exit = $false

$memarr = @([int]0) * 65536
$codarr = $code + @([char][int]0) * 66536 + @([char]'q')

While($exit -eq $false){

$ccode = $codarr[$exptr]

switch($ccode){
    '+' {$memarr[$meptr]++;if($memarr[$meptr] -lt 0){$memarr[$meptr] = 0};$exptr++}
    '-' {$memarr[$meptr]--;if($memarr[$meptr] -lt 0){$memarr[$meptr] = 0};$exptr++}
    '>' {$meptr++;if($meptr -lt 0){$meptr=0};$exptr++}
    '<' {$meptr--;if($meptr -lt 0){$meptr=0};$exptr++}
    '[' {

         $cchcode = ''
         $cycptr = $exptr
         $cyclelev = 1

         if($memarr[$meptr] -ne 0){$cyclelev = 0;$cycptr++}

         while ($cyclelev -ne 0){
             $cycptr++
             if($codarr[$cycptr] -eq '['){$cyclelev++}
             if($codarr[$cycptr] -eq ']'){$cyclelev--}
            }

         $exptr = $cycptr
        }
    ']' {
         $cchcode = ''
         $cycptr = $exptr
         $cyclelev = 1

         if($memarr[$meptr] -eq 0){$cyclelev = 0;$cycptr++}

         while ($cyclelev -ne 0){
             $cycptr--
             if($codarr[$cycptr] -eq ']'){$cyclelev++}
             if($codarr[$cycptr] -eq '['){$cyclelev--}
            }

         $exptr = $cycptr
        }
    ',' {$memarr[$meptr] = [int]([Console]::ReadKey()).KeyChar; if($memarr[$meptr] -eq 13){''};$exptr++}
    '.' {[Console]::Write([string][char]$memarr[$meptr]); if($memarr[$meptr] -eq 13){''};$exptr++}
    's' {$rwptr = $memarr[$meptr];$exptr++}
    'j' {$exptr = $memarr[$meptr]}
    'm' {$codarr[$rwptr] = [char]$memarr[$meptr];$exptr++}
    'g' {$memarr[$meptr] = [int]$codarr[$rwptr];$exptr++}
    'q' {$exit = $true}
    default {$exptr++}
    }
}