39 lines
1.3 KiB
C#
39 lines
1.3 KiB
C#
namespace AOC2015;
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/// <summary>
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/// Day 9: <a href="https://adventofcode.com/2015/day/9"/>
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/// </summary>
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public sealed class Day09() : Day(2015, 9, "All in a Single Night")
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{
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private readonly List<Distance> _distances = [];
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private int _shortest = int.MaxValue, _longest;
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public override void ProcessInput()
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{
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foreach (var split in Input.Select(line => line.Split(' ')))
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{
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_distances.Add(new(split[0], split[2], int.Parse(split[4])));
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_distances.Add(new(split[2], split[0], int.Parse(split[4])));
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}
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var cities = _distances.Select(d => d.Start).Distinct().ToList();
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var routes = cities.Permute();
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foreach (var permutation in routes.Select(p => p.ToList()))
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{
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var routeLength = 0;
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for (var i = 1; i < permutation.Count; i++)
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routeLength += _distances.First(d => d.Start == permutation[i - 1] && d.End == permutation[i]).Length;
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if (routeLength < _shortest) _shortest = routeLength;
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if (routeLength > _longest) _longest = routeLength;
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}
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}
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public override object Part1() => _shortest;
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public override object Part2() => _longest;
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private record Distance(string Start, string End, int Length);
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}
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