40 lines
982 B
C#
40 lines
982 B
C#
using System.Security.Cryptography;
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namespace AOC2015;
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/// <summary>
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/// Day 4: <a href="https://adventofcode.com/2015/day/4"/>
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/// </summary>
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public sealed class Day04() : Day(2015, 4, "The Ideal Stocking Stuffer")
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{
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private string? _key;
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public override void ProcessInput() => _key = Input.First();
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public override object Part1()
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{
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var counter = 0;
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while (true)
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{
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var hash = MD5.HashData(Encoding.ASCII.GetBytes(_key + counter));
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if (BitConverter.ToString(hash).Replace("-", "").StartsWith("00000"))
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return counter;
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counter++;
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}
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}
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public override object Part2()
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{
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var counter = 9_000_000;
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while (true)
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{
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var hashBytes = MD5.HashData(Encoding.ASCII.GetBytes(_key + counter));
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if (hashBytes[0] == 0 && hashBytes[1] == 0 && hashBytes[2] == 0)
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return counter;
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counter++;
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}
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}
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}
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