Advent of Code 2022 Day 6 - Discussions

Questions & Discussions Coding Challenges
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This topic is about Day 6 of the Advent of Code 2022 .

Sorry for the delay in opening this post. Hope we already have some solutions to day 6

Link to our leaderboard:

https://adventofcode.com/2022/leaderboard/private/view/370884

The entry code is:
370884-a6a71927

Good luck!

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I feel like we got an easy challenge today, and should be prepared for something tricky next time :slight_smile:

main(File) ->
    {ok, RawData} = file:read_file(File),
    Data = binary_to_list(RawData),
    io:format("part 1: ~p~n", [solve1(Data)]),
    io:format("part 2: ~p~n", [solve2(Data)]).

solve1(Data) ->
    solve(Data, 4, 0).

solve2(Data) ->
    solve(Data, 14, 0).

solve(List, N, Pos) ->
    {Set, _} = lists:split(N, List),
    case sets:size(sets:from_list(Set)) of
        N -> Pos + N;
        _ -> solve(tl(List), N, Pos + 1)
    end.
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Yeah it was easy! And I think I will do all remaining problems in Erlang now. Never thought I’d feel this at home this early.

-module(day_6).

-export([solve/0]).

input() ->
  {ok, DataStream} = file:read_file("data/6.txt"),
  DataStream.

solve() ->
  ParsedStream = binary:bin_to_list(input()),
  {solve1(ParsedStream), solve2(ParsedStream)}.

solve1(ParsedStream) ->
  solve_for(ParsedStream, 4, 0).

solve2(ParsedStream) ->
  solve_for(ParsedStream, 14, 0).

solve_for(ParsedStream, BufferSize, Counter) ->
  {Buffer, _} = lists:split(BufferSize, ParsedStream),
  case unique_members(Buffer) of
    true ->
      Counter + BufferSize;
    false ->
      solve_for(tl(ParsedStream), BufferSize, Counter + 1)
  end.

unique_members(List) ->
  length(List) == length(ordsets:from_list(List)).
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Wow that was clever how you managed the uniqueness :smiley:

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