commit 775fa1f105d30241a38ebaf1cfe82b8d33c1535b · hauleth.dev/advent-of-code

+327

2024/day08.livemd

···

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       <!-- livebook:{"persist_outputs":true} -->

     

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       # Day 08

     

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       ```elixir

     

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       Mix.install([:kino_aoc])

     

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       ```

     

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       ## Section

     

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       <!-- livebook:{"attrs":"eyJhc3NpZ25fdG8iOiJwdXp6bGVfaW5wdXQiLCJkYXkiOiI4Iiwic2Vzc2lvbl9zZWNyZXQiOiJBRFZFTlRfT0ZfQ09ERV9TRVNTSU9OIiwieWVhciI6IjIwMjQifQ","chunks":null,"kind":"Elixir.KinoAOC.HelperCell","livebook_object":"smart_cell"} -->

     

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       ```elixir

     

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       {:ok, puzzle_input} =

     

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         KinoAOC.download_puzzle("2024", "8", System.fetch_env!("LB_ADVENT_OF_CODE_SESSION"))

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       {:ok,

     

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        "..........M..........j.............y.....O........\n...B...............q......m........lGO............\n....................q......2.l.GQ...O.............\n.....X.......................................4....\n.....................q............................\n....M......P...............xl.K.............2.....\n....F.........L.......C.K..............m..........\n..........FM......P....jy......m..........o...r...\n..X.......P.....RL..............G..x..........4...\n............L..........NC.....q...................\n.....C.X...............K....y..........4..........\n........S...R.............j.x.....V...4...........\n.....................R..x.....V..i......m.........\n...........................R.V......N.......X.....\n.....F.........M......N......E....................\n................v................T.......F......O.\n.............................N...V.......Q........\n...v.....................C.....i..................\n......c.....W..n.w........................E.......\n3...................c.....................Q..6....\n...........h......................j...............\n.......n.0......h.................E..............2\n.v.............7.......120.....c..................\n......n.0............w...........D.t.........E...r\n....8..3......0.w.hP....z...D..T...............r..\n.................f........T........G......eQ......\n......f.n.....7..p................................\n.....Y..7.......f......I......D......K............\n............Uf....T..W.....D..r...i...............\n......I...............................Z...........\n....5....B.......b..............s..............Z..\n..........d...W..Uwh.............c..........i.....\n..I.3..Y......................e...................\n.....p.b..........k......7........................\np...........k....I..b..........s..................\n.....k.......o...........W........................\n.A..Y..........U.................a........6.......\n..A...Y.p...................................6.....\nB......k..........................Z............u..\n...3.....................s..............a.........\n......A.........................g.....a...........\n.......A....8...b.U......H....sS..................\n.........................S1.............t.........\n.....................9z..e.....5..1.g.u...........\n.......................z....d....g....H.J....o.6..\n........B................d.....u....9.J.H.........\n.8........S.................u9.............J.....H\n.....................Z5.............t1...........a\n.....................e..v...................o..t..\n.....8...............L.....z.............J........"}

     

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       ```

     

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       ```elixir

     

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       # puzzle_input =

     

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       """

     

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       ............

     

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       ........0...

     

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       .....0......

     

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       .......0....

     

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       ....0.......

     

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       ......A.....

     

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       ............

     

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       ............

     

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       ........A...

     

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       .........A..

     

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       ............

     

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       ............

     

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       """

     

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       freqs =

     

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         puzzle_input

     

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         |> String.split("\n", trim: true)

     

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         |> Enum.with_index()

     

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         |> Enum.flat_map(fn {row, y} ->

     

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           row

     

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           |> String.to_charlist()

     

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           |> Enum.with_index()

     

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           |> Enum.filter(fn {freq, _} -> freq != ?. end)

     

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           |> Enum.map(fn {freq, x} -> {{x, y}, freq} end)

     

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         end)

     

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         |> Map.new()

     

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         |> Enum.group_by(&elem(&1, 1), &elem(&1, 0))

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       warning: code block contains unused literal "............\n........0...\n.....0......\n.......0....\n....0.......\n......A.....\n............\n............\n........A...\n.........A..\n............\n............\n" (remove the literal or assign it to _ to avoid warnings)

     

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       └─ Workspace/hauleth/advent-of-code/2024/day08.livemd#cell:y5uv5vxll4fey6gh:1

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       %{

     

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         117 => [{28, 46}, {31, 45}, {38, 43}, {47, 38}],

     

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         73 => [{2, 32}, {17, 34}, {23, 27}, {6, 29}],

     

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         89 => [{4, 36}, {7, 32}, {6, 37}, {5, 27}],

     

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         48 => [{25, 22}, {9, 21}, {8, 23}, {14, 24}],

     

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         57 => [{29, 46}, {21, 43}, {36, 45}],

     

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         113 => [{30, 9}, {20, 2}, {21, 4}, {19, 1}],

     

       75
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         69 => [{42, 18}, {34, 21}, {45, 23}, {29, 14}],

     

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         88 => [{7, 10}, {5, 3}, {44, 13}, {2, 8}],

     

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         100 => [{25, 45}, {28, 44}, {10, 31}],

     

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         71 => [{36, 1}, {35, 25}, {31, 2}, {32, 8}],

     

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         98 => [{16, 41}, {7, 33}, {20, 34}, {17, 30}],

     

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         81 => [{42, 19}, {41, 16}, {43, 25}, {32, 2}],

     

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         76 => [{12, 9}, {14, 6}, {17, 8}, {21, 49}],

     

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         85 => [{15, 36}, {12, 28}, {17, 31}, {18, 41}],

     

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         120 => [{27, 5}, {35, 8}, {28, 11}, {24, 12}],

     

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         109 => [{26, 1}, {39, 6}, {40, 12}, {31, 7}],

     

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         72 => [{38, 44}, {40, 45}, {49, 46}, {25, 41}],

     

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         110 => [{8, 26}, {7, 21}, {15, 18}, {6, 23}],

     

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         68 => [{30, 27}, {28, 24}, {27, 28}, {33, 23}],

     

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         86 => [{29, 13}, {33, 16}, {30, 12}, {34, 11}],

     

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         116 => [{35, 23}, {36, 47}, {47, 48}, {40, 42}],

     

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         51 => [{7, 24}, {0, 19}, {3, 39}, {4, 32}],

     

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         80 => [{18, 7}, {19, 24}, {10, 8}, {11, 5}],

     

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         77 => [{11, 7}, {15, 14}, {10, 0}, {4, 5}],

     

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         78 => [{22, 14}, {29, 16}, {36, 13}, {23, 9}],

     

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         108 => [{29, 2}, {28, 5}, {35, 1}],

     

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         103 => [{32, 40}, {36, 43}, {33, 44}],

     

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         122 => [{27, 49}, {23, 44}, {24, 24}, {22, 43}],

     

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         83 => [{10, 46}, {25, 42}, {31, 41}, {8, 11}],

     

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         74 => [{38, 45}, {41, 49}, {43, 46}, {40, 44}],

     

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         99 => [{31, 22}, {33, 31}, {20, 19}, {6, 18}],

     

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         112 => [{5, 33}, {17, 26}, {8, 37}, {0, 34}],

     

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         97 => [{38, 40}, {33, 36}, {49, 47}, {40, 39}],

     

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         104 => [{16, 21}, {19, 31}, {11, 20}, {18, 24}],

     

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         75 => [{30, 5}, {24, 6}, {23, 10}, {37, 27}],

     

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         90 => [{21, 47}, {47, 30}, {34, 38}, {38, 29}],

     

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         55 => [{15, 22}, {14, 26}, {8, 27}, {25, 33}],

     

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         52 => [{45, 3}, {38, 11}, {39, 10}, {46, 8}],

     

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         111 => [{13, 35}, {42, 7}, {45, 44}, {44, 48}],

     

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         87 => [{25, 35}, {12, 18}, {14, 31}, {21, 28}],

     

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         119 => [{21, 23}, {18, 31}, {17, 18}, {16, 24}],

     

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         82 => [{12, 11}, {27, 13}, {21, 12}, {16, 8}],

     

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         53 => [{22, 47}, {31, 43}, {4, 30}],

     

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         50 => [{27, 2}, {24, 22}, {44, 5}, {49, 21}],

     

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         66 => [{8, 45}, {9, 30}, {3, 1}, {0, ...}],

     

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         70 => [{5, 14}, {41, 15}, {10, ...}, {...}],

     

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         56 => [{12, 41}, {4, ...}, {...}, ...],

     

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         102 => [{17, ...}, {...}, ...],

     

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         105 => [{...}, ...],

     

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         121 => [...],

     

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         ...

     

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       }

     

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       ```

     

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       ```elixir

     

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       {w, h} =

     

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         puzzle_input

     

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         |> String.split("\n", trim: true)

     

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         |> then(fn [a | _] = lst ->

     

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           {byte_size(a), length(lst)}

     

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         end)

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       {50, 50}

     

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       ```

     

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       ```elixir

     

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       defmodule Antennas do

     

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         def each_pair([]), do: []

     

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         def each_pair([a | rest]) do

     

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           for(b <- rest, do: {a, b}) ++ each_pair(rest)

     

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         end

     

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         def antinodes({xa, ya}, {xb, yb}) do

     

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           dx = xa - xb

     

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           dy = ya - yb

     

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           Stream.from_index()

     

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           |> Stream.flat_map(fn n ->

     

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             dx = dx * n

     

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             dy = dy * n

     

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             [{xa + dx, ya + dy}, {xb - dx, yb - dy}]

     

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           end)

     

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         end

     

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       end

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       {:module, Antennas, <<70, 79, 82, 49, 0, 0, 10, ...>>, {:antinodes, 2}}

     

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       ```

     

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       ## Part 1

     

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       ```elixir

     

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       antinodes =

     

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         for {_, antennas} <- freqs,

     

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             {a, b} <- Antennas.each_pair(antennas),

     

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             {x, y} = node <- Antennas.antinodes(a, b) |> Stream.drop(2) |> Enum.take(2),

     

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             x in 0..(w - 1) and y in 0..(h - 1),

     

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             into: MapSet.new() do

     

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           node

     

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         end

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       MapSet.new([

     

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         {20, 41},

     

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         {20, 3},

     

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         {16, 10},

     

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         {26, 21},

     

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         {6, 18},

     

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         {10, 32},

     

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         {20, 30},

     

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         {33, 17},

     

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         {17, 30},

     

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         {29, 28},

     

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         {40, 35},

     

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         {28, 37},

     

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         {25, 49},

     

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         {10, 19},

     

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         {14, 17},

     

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         {35, 7},

     

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         {29, 48},

     

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         {1, 34},

     

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         {23, 8},

     

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         {35, 6},

     

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         {49, 17},

     

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         {46, 38},

     

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         {5, 39},

     

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         {37, 29},

     

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         {16, 15},

     

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         {48, 41},

     

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         {4, 18},

     

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         {24, 15},

     

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         {33, 44},

     

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         {39, 18},

     

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         {40, 25},

     

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         {35, 21},

     

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         {41, 17},

     

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         {20, 37},

     

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         {45, 24},

     

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         {0, 35},

     

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         {18, 3},

     

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         {1, 36},

     

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         {35, 41},

     

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         {37, 28},

     

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         {28, 15},

     

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         {29, 38},

     

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         {46, 43},

     

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         {31, 19},

     

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         {19, 39},

     

       227
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         {43, 10},

     

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         {38, 10},

     

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         {21, 26},

     

       230
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         {28, ...},

     

       231
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         {...},

     

       232
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         ...

     

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       ])

     

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       ```

     

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       ```elixir

     

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       MapSet.size(antinodes)

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       398

     

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       ```

     

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       ## Part 2

     

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       ```elixir

     

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       antinodes_res =

     

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         for {_, antennas} <- freqs,

     

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             {a, b} <- Antennas.each_pair(antennas),

     

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             {x, y} = node <- Enum.take(Antennas.antinodes(a, b), 100),

     

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             x in 0..(w - 1) and y in 0..(h - 1),

     

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             into: MapSet.new() do

     

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           node

     

       256
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         end

     

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       ```

     

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       <!-- livebook:{"output":true} -->

     

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       ```

     

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       MapSet.new([

     

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         {37, 47},

     

       264
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         {35, 30},

     

       265
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         {4, 5},

     

       266
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         {20, 41},

     

       267
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         {31, 42},

     

       268
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         {9, 34},

     

       269
       +
         {47, 38},

     

       270
       +
         {20, 3},

     

       271
       +
         {47, 44},

     

       272
       +
         {22, 36},

     

       273
       +
         {45, 7},

     

       274
       +
         {19, 38},

     

       275
       +
         {27, 21},

     

       276
       +
         {9, 33},

     

       277
       +
         {16, 10},

     

       278
       +
         {21, 45},

     

       279
       +
         {26, 21},

     

       280
       +
         {21, 48},

     

       281
       +
         {16, 38},

     

       282
       +
         {35, 26},

     

       283
       +
         {28, 20},

     

       284
       +
         {45, 19},

     

       285
       +
         {27, 22},

     

       286
       +
         {16, 24},

     

       287
       +
         {6, 18},

     

       288
       +
         {10, 32},

     

       289
       +
         {33, 15},

     

       290
       +
         {36, 14},

     

       291
       +
         {20, 30},

     

       292
       +
         {33, 17},

     

       293
       +
         {41, 1},

     

       294
       +
         {36, 25},

     

       295
       +
         {28, 48},

     

       296
       +
         {5, 9},

     

       297
       +
         {14, 16},

     

       298
       +
         {17, 30},

     

       299
       +
         {30, 49},

     

       300
       +
         {32, 18},

     

       301
       +
         {29, 28},

     

       302
       +
         {40, 35},

     

       303
       +
         {6, 23},

     

       304
       +
         {17, 39},

     

       305
       +
         {28, 37},

     

       306
       +
         {6, 29},

     

       307
       +
         {39, 23},

     

       308
       +
         {49, 16},

     

       309
       +
         {34, 0},

     

       310
       +
         {11, 37},

     

       311
       +
         {25, ...},

     

       312
       +
         {...},

     

       313
       +
         ...

     

       314
       +
       ])

     

       315
       +
       ```

     

       316
       +
       

     

       317
       +
       ```elixir

     

       318
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       MapSet.size(antinodes_res)

     

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       +
       ```

     

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       <!-- livebook:{"output":true} -->

     

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       +
       

     

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       ```

     

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       1333

     

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       ```

     

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       <!-- livebook:{"offset":9159,"stamp":{"token":"XCP.vUy-wiQ1Ola4DEyyjRWCHAhmtmjmoDVd4jyZ0g5rhe0RM8-OKii82hOqtdVQ6B_yetZ17Z8avgol_Frq-whc91b45zMSMIRVIC-azF_IQmYLdHX0p3LEQ0xKLcBUuir19OQ","version":2}} -->