40 lines
1.0 KiB
C#
40 lines
1.0 KiB
C#
using System.Collections.Generic;
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using System.Linq;
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namespace aoc2019
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{
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internal sealed class Day6 : Day
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{
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private readonly Dictionary<string, string> input;
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public Day6()
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{
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input = Input.ToDictionary(i => i.Split(')')[1], i => i.Split(')')[0]);
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}
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public override int DayNumber => 6;
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private List<string> GetParents(string obj)
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{
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var res = new List<string>();
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for (var curr = obj; curr != "COM"; curr = input[curr])
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res.Add(curr);
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res.Add("COM");
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return res;
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}
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public override string Part1()
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{
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return $"{input.Keys.Sum(o => GetParents(o).Count - 1)}";
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}
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public override string Part2()
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{
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var you = GetParents("YOU");
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var san = GetParents("SAN");
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var common = 1;
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for (; you[^common] == san[^common]; common++) ;
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return $"{you.Count + san.Count - common * 2}";
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}
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}
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} |