$0 = 0
$2 = 0
while($2 == 0)
	$3 = $0 / W
	$4 = $0 % W
	$3 = $3 + 1
	$4 = $4 + 1
	$2 = A[$3,$4] - B[$3,$4]
	$0 = $0 + 1
end
$0 = $0 - 1
$3 = $0 / W
$4 = $0 % W
$3 = $3 + 1
$4 = $4 + 1
return($3,$4)