$1 = 0
while($1 <= W * H)
  $11 = $1%W
  $12 = $1//W
  $3 = A[$11+1,$12*1]
  $4 = B[$11+1,$12+1]
  $5 = $3 - $4
  $6 = $5 - 1
  $7 = $5 // $6
  $10 = $7 * $1
end
$11 = $1%W
$12 = $1//W
return ($11+1,$12+1)