eldridge.cam
Advent of Code solutions
2021 day 20
+55
2021/20/p1.tri
+55
2021/20/p1.tri
···
···
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import "trilogy:debug" use dbg
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import "trilogy:io" use readline, readall
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import "trilogy:parsec" use parse, apply, repeat, char_of, per_line, many_1
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import "trilogy:array" as array use map
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import "trilogy:bits" as bits
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import "trilogy:number" as number
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import "trilogy:core" use length
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import "trilogy:iterator" as it
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func infinite_image true cb = with cb!() { when 'outside resume 0bb111 }
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func infinite_image false cb = with cb!() { when 'outside resume 0bb000 }
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proc read_at!(image, row, col) {
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let outside = yield 'outside
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let unpadded = with image.row { when 'mia { return outside } }
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let padded = bits::concat outside <| bits::concat unpadded outside
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return (padded <~ (col + 3)) ~>> (length padded - 3)
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}
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func read_around image row col = {
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let a = read_at!(image, row - 1, col - 1)
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let b = read_at!(image, row, col - 1)
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let c = read_at!(image, row + 1, col - 1)
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number::from (a | b ~~> 3 | c ~~> 6)
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}
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func enhance_row enhancement image row =
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it::range (-1) (length (image.0))
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|> it::map (read_around image row)
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|> it::map ((.) enhancement)
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|> bits::collect
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func enhance outside enhancement image = {
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using infinite_image outside
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let enhanced = it::range (-1) (length image)
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|> it::map (enhance_row enhancement image)
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|> array::collect
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let new_outside = enhancement.(read_around image (-3) (-3))
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new_outside:enhanced
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}
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proc main!() {
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let enhancement = readline!()
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|> parse (repeat 512 (char_of ".#"))
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|> map ((==) '#')
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|> bits::from_array
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let "\n" = readline!()
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let image = readall!()
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|> parse (per_line (many_1 (char_of ".#")))
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|> map (bits::from_array << map ((==) '#'))
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let outside:enhanced = enhance false enhancement image
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let _:enhanced_2 = enhance outside enhancement enhanced
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dbg!(array::reduce (+) <| map bits::pop_count enhanced_2)
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exit 0
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}
+61
2021/20/p2.tri
+61
2021/20/p2.tri
···
···
1
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import "trilogy:debug" use dbg
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import "trilogy:io" use readline, readall
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import "trilogy:parsec" use parse, apply, repeat, char_of, per_line, many_1
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import "trilogy:array" as array use map
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import "trilogy:bits" as bits
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import "trilogy:number" as number
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import "trilogy:core" use length
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import "trilogy:iterator" as it
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func infinite_image true cb = with cb!() { when 'outside resume 0bb111 }
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func infinite_image false cb = with cb!() { when 'outside resume 0bb000 }
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proc read_at!(image, row, col) {
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let outside = yield 'outside
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let unpadded = with image.row { when 'mia { return outside } }
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let padded = bits::concat outside <| bits::concat unpadded outside
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return (padded <~ (col + 3)) ~>> (length padded - 3)
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}
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func read_around image row col = {
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let a = read_at!(image, row - 1, col - 1)
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let b = read_at!(image, row, col - 1)
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let c = read_at!(image, row + 1, col - 1)
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number::from (a | b ~~> 3 | c ~~> 6)
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}
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func enhance_row enhancement image row =
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it::range (-1) (length (image.0))
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|> it::map (read_around image row)
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|> it::map ((.) enhancement)
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|> bits::collect
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func enhance outside enhancement image = {
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using infinite_image outside
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let enhanced = it::range (-1) (length image)
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|> it::map (enhance_row enhancement image)
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|> array::collect
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let new_outside = enhancement.(read_around image (-3) (-3))
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new_outside:enhanced
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}
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proc main!() {
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let enhancement = readline!()
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|> parse (repeat 512 (char_of ".#"))
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|> map ((==) '#')
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|> bits::from_array
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let "\n" = readline!()
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let mut image = readall!()
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|> parse (per_line (many_1 (char_of ".#")))
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|> map (bits::from_array << map ((==) '#'))
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let mut outside = false
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let mut i = 0
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while i < 50 {
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let outside_2:image_2 = enhance outside enhancement image
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outside = outside_2
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image = image_2
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i += 1
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}
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dbg!(array::reduce (+) <| map bits::pop_count image)
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exit 0
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}