50 lines
1.1 KiB
C#
50 lines
1.1 KiB
C#
namespace AOC2015;
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/// <summary>
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/// Day 10: <a href="https://adventofcode.com/2015/day/10"/>
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/// </summary>
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public sealed class Day10() : Day(2015, 10, "Elves Look, Elves Say")
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{
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private string? _seed;
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public override void ProcessInput() => _seed = Input.First();
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public override object Part1()
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{
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for (var i = 0; i < 40; i++)
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_seed = string.Concat(LookAndSay(_seed!));
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return _seed!.Length;
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}
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public override object Part2()
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{
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for (var i = 0; i < 10; i++)
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_seed = string.Concat(LookAndSay(_seed!));
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return _seed!.Length;
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}
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private static IEnumerable<int> LookAndSay(string data)
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{
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var currentDigit = data[0];
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int count = 1, place = 1;
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while (place < data.Length)
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{
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if (data[place] == currentDigit) count++;
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else
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{
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yield return count;
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yield return currentDigit - '0';
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currentDigit = data[place];
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count = 1;
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}
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place++;
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}
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yield return count;
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yield return currentDigit - '0';
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}
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} |