code:

---

function arraycomp($a1, $a2, optional $m)
 dim $s
 for each $n in $a2
  if (ascan($a1,$n)>-1 and $m) or (ascan($a1,$n)=-1 and 0=$m) $s=$s+' '+$n endif
 next
 $arraycomp = split( substr($s,2,len($s)) )
endfunction

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