5c2c9af4 ​

input = fill #0 (fill #1 black) |> fold (λr. rect ((r.1, r.2, r.1, r.2), #2)) #3
output = fill 23v (fill 23h black) |> fold (fold rect) #4
(VInt, HInt, Color, UList (VInt, HInt), OList UList ((VInt, HInt, VInt, HInt), Color))
(23v, 23h, teal, {(9v, 18h), (6v, 15h), (3v, 12h)}, [{((1v, 3h, 18v, 23h), teal)}, {((1v, 4h, 17v, 23h), black)}, {((1v, 6h, 15v, 23h), teal)}, {((1v, 7h, 14v, 23h), black)}, {((1v, 9h, 12v, 21h), teal)}, {((1v, 10h, 11v, 20h), black)}, {((3v, 12h, 9v, 18h), teal)}, {((4v, 13h, 8v, 17h), black)}, {((21v, 1h, 21v, 23h), teal), ((6v, 15h, 6v, 15h), teal)}])
(23v, 23h, red, {(16v, 10h), (14v, 12h), (12v, 14h)}, [{((4v, 2h, 23v, 22h), red)}, {((5v, 3h, 23v, 21h), black)}, {((6v, 4h, 22v, 20h), red)}, {((7v, 5h, 21v, 19h), black)}, {((8v, 6h, 20v, 18h), red)}, {((9v, 7h, 19v, 17h), black)}, {((10v, 8h, 18v, 16h), red)}, {((11v, 9h, 17v, 15h), black)}, {((12v, 10h, 16v, 14h), red)}, {((13v, 11h, 15v, 13h), black)}, {((2v, 1h, 2v, 23h), red), ((14v, 12h, 14v, 12h), red)}])
(23v, 23h, green, {(13v, 5h), (9v, 9h), (5v, 13h)}, [{((1v, 1h, 21v, 21h), green)}, {((1v, 1h, 20v, 20h), black)}, {((1v, 1h, 17v, 17h), green)}, {((2v, 2h, 16v, 16h), black)}, {((5v, 5h, 13v, 13h), green)}, {((6v, 6h, 12v, 12h), black)}, {((9v, 9h, 9v, 9h), green)}])
(28v, 28h, yellow, {(25v, 20h), (19v, 14h), (13v, 8h)}, ?)