3befdf3e ​

input = fill #0 (fill #1 black) |> fold (λr. rect ((r.1 - 1, r.2 - 1, r.3 + 1, r.4 + 1), #2)) #4 |> fold (λr. rect (r, #3)) #4
output = fill 10v (fill 10h black) |> fold (λr. rect ((4v, r.2 - 1, r.3 + 1, r.4 + 1), #3)) #4 |> fold (λr. rect ((4v, r.1, #5, r.2), #2)) #6 |> fold (λr. rect ((r.1, #8, r.2, #7), #2)) #9 |> fold (λr. rect ((5v, r.2, r.3, r.4), #2)) #4
(VInt, HInt, Color, Color, UList (VInt, HInt, VInt, HInt), VInt, UList (HInt, HInt), HInt, HInt, UList (VInt, VInt))
(10v, 10h, yellow, fuschia, {(5v, 5h, 5v, 5h)}, 6v, {(7h, 7h), (3h, 3h)}, 6h, 4h, {(7v, 7v), (3v, 3v)})
(10v, 10h, red, orange, {(5v, 5h, 6v, 6h)}, 7v, {(8h, 9h), (2h, 3h)}, 7h, 4h, {(8v, 9v), (2v, 3v)})
(10v, 10h, green, blue, {(5v, 4h, 6v, 5h)}, 7v, {(1h, 2h), (7h, 8h)}, 6h, 3h, {(8v, 9v), (2v, 3v)})
(12v, 12h, teal, green, {(8v, 8h, 9v, 9h), (3v, 3h, 3v, 3h)}, ?, ?, ?, ?, ?)