b6afb2da ​

input = fill 10v (fill 10h black) |> rect ((#0, #1, 10v, 10h), grey) |> rect ((#2, 7 - #4, #3, #4), grey)
output = fill 10v (fill 10h black) |> fold rect #5
(VInt, HInt, VInt, VInt, HInt, UList ((VInt, HInt, VInt, HInt), Color))
(6v, 7h, 3v, 6v, 5h, {((10v, 10h, 10v, 10h), blue), ((10v, 8h, 10v, 9h), yellow), ((10v, 7h, 10v, 7h), blue), ((7v, 10h, 9v, 10h), yellow), ((6v, 10h, 6v, 10h), blue), ((7v, 8h, 9v, 9h), red), ((7v, 7h, 9v, 7h), yellow), ((6v, 8h, 6v, 9h), yellow), ((6v, 7h, 6v, 7h), blue), ((6v, 5h, 6v, 5h), blue), ((6v, 3h, 6v, 4h), yellow), ((6v, 2h, 6v, 2h), blue), ((4v, 5h, 5v, 5h), yellow), ((4v, 2h, 5v, 2h), yellow), ((3v, 5h, 3v, 5h), blue), ((3v, 3h, 3v, 4h), yellow), ((3v, 2h, 3v, 2h), blue), ((4v, 3h, 5v, 4h), red)})
(7v, 5h, 1v, 5v, 6h, {((10v, 10h, 10v, 10h), blue), ((10v, 6h, 10v, 9h), yellow), ((10v, 5h, 10v, 5h), blue), ((8v, 10h, 9v, 10h), yellow), ((7v, 10h, 7v, 10h), blue), ((5v, 1h, 5v, 1h), blue), ((2v, 1h, 4v, 1h), yellow), ((1v, 6h, 1v, 6h), blue), ((1v, 2h, 1v, 5h), yellow), ((1v, 1h, 1v, 1h), blue), ((8v, 6h, 9v, 9h), red), ((8v, 5h, 9v, 5h), yellow), ((7v, 6h, 7v, 9h), yellow), ((7v, 5h, 7v, 5h), blue), ((5v, 6h, 5v, 6h), blue), ((5v, 2h, 5v, 5h), yellow), ((2v, 6h, 4v, 6h), yellow), ((2v, 2h, 4v, 5h), red)})
(8v, 5h, 1v, 6v, 5h, ?)