$0 = 0
while($0 < H * W)
  $1 = $0 / W + 1
  $2 = $0 % W + 1
  $3 = $3 + A[$1,$2] - B[$1,$2]
  $0 = $0 + 1
end
$0 = 0
while($0 < H * W)
  $1 = $0 / W + 1
  $2 = $0 % W + 1
  $4 = $4 + (A[$1,$2] - B[$1,$2]) * $0
  $0 = $0 + 1
end
$4 = $4 / $3
$5 = $4 / W + 1
$6 = $4 % W + 1
return($5, $6)