[Kazun]

Код:

$a = 1,2,3
$b = 3,4,5

Compare-Object $a $b -IncludeEqual -ExcludeDifferent

InputObject SideIndicator
----------- -------------
          3 ==

$r = Compare-Object $a $b -IncludeEqual -ExcludeDifferent
if($r) {
    "Код"
}