a9f96cdd ​

input = fill 3v (fill 5h black) |> rect ((#0, #1, #0, #1), red)
output = fill 3v (fill 5h black) |> fold (λr. rect ((r.2, r.3, r.2, r.3), r.1)) #2
(VInt, HInt, UList (Color, VInt, HInt))
(2v, 2h, {(orange, 3v, 3h), (teal, 3v, 1h), (fuschia, 1v, 3h), (green, 1v, 1h)})
(3v, 5h, {(green, 2v, 4h)})
(1v, 3h, {(orange, 2v, 4h), (teal, 2v, 2h)})
(2v, 4h, {(orange, 3v, 5h), (teal, 3v, 3h), (fuschia, 1v, 5h), (green, 1v, 3h)})
(2v, 5h, ?)