135 lines
4.2 KiB
C#
135 lines
4.2 KiB
C#
using System;
|
|
using System.Collections.Generic;
|
|
using System.Data.Common;
|
|
using System.IO;
|
|
using System.Linq;
|
|
using AdvenOfCode.Contracts;
|
|
using Coordinate = (int x, int y, int z);
|
|
|
|
namespace AoC_2025;
|
|
|
|
public class Day08
|
|
{
|
|
private Coordinate[] ParsePuzzleInput(string path)
|
|
{
|
|
var puzzleInput = File.ReadAllLines(path)
|
|
.Where(line => !string.IsNullOrWhiteSpace(line))
|
|
.Select(line => line.Split(',', StringSplitOptions.RemoveEmptyEntries).Select(str => int.Parse(str)).ToArray())
|
|
.Select(numbers => (numbers[0], numbers[1], numbers[2]))
|
|
.ToArray();
|
|
return puzzleInput;
|
|
}
|
|
|
|
public long SolvePart1(string pathToPuzzleInput, int amountToConnect)
|
|
{
|
|
var points = ParsePuzzleInput(pathToPuzzleInput);
|
|
|
|
var pointPairs = GetAllCombinationsSortedByDistance(points);
|
|
|
|
var circuits = CombineCircuits(amountToConnect, points, pointPairs);
|
|
|
|
return circuits
|
|
.Select(circuit => circuit.Count)
|
|
.OrderDescending()
|
|
.Take(3)
|
|
.Aggregate((acc, next) => acc * next);
|
|
}
|
|
|
|
public long SolvePart2(string pathToPuzzleInput)
|
|
{
|
|
var points = ParsePuzzleInput(pathToPuzzleInput);
|
|
|
|
var pointPairs = GetAllCombinationsSortedByDistance(points);
|
|
|
|
var lastConnected = LastCombinedConnectAllCircuits(points, pointPairs);
|
|
|
|
return lastConnected.a.x * lastConnected.b.x;
|
|
}
|
|
|
|
private List<List<Coordinate>> CombineCircuits(int amountToConnect, Coordinate[] points,
|
|
(Coordinate pointA, Coordinate pointB)[] pointPairs)
|
|
{
|
|
var circuits = points.Select(p => new List<Coordinate>() { p }).ToList();
|
|
for (var i = 0; i < amountToConnect; i++)
|
|
{
|
|
var nextToConnect = pointPairs[i];
|
|
circuits = AddToCircuits(nextToConnect.pointA, nextToConnect.pointB, circuits);
|
|
}
|
|
|
|
return circuits;
|
|
}
|
|
|
|
private (Coordinate a, Coordinate b) LastCombinedConnectAllCircuits(Coordinate[] points,
|
|
(Coordinate pointA, Coordinate pointB)[] pointPairs)
|
|
{
|
|
var circuits = points.Select(p => new List<Coordinate>() { p }).ToList();
|
|
var lastConnected = pointPairs.First();
|
|
var i = 0;
|
|
while(circuits.Count > 1)
|
|
{
|
|
var nextToConnect = pointPairs[i++];
|
|
circuits = AddToCircuits(nextToConnect.pointA, nextToConnect.pointB, circuits);
|
|
lastConnected = nextToConnect;
|
|
}
|
|
|
|
return lastConnected;
|
|
}
|
|
|
|
private double GetDistance(Coordinate a, Coordinate b)
|
|
{
|
|
return Math.Sqrt(Math.Pow(a.x - b.x, 2) + Math.Pow(a.y - b.y, 2) + Math.Pow(a.z - b.z, 2));
|
|
}
|
|
|
|
private List<List<Coordinate>> AddToCircuits(Coordinate a, Coordinate b, List<List<Coordinate>> circuits)
|
|
{
|
|
var circuitToAddBTo = circuits.FirstOrDefault(circuit => circuit.Contains(a));
|
|
var circuitToAddATo = circuits.FirstOrDefault(circuit => circuit.Contains(b));
|
|
if (circuitToAddATo == null && circuitToAddBTo == null)
|
|
{
|
|
circuits.Add([a, b]);
|
|
return circuits;
|
|
}
|
|
|
|
if (circuitToAddATo == circuitToAddBTo)
|
|
{
|
|
return circuits;
|
|
}
|
|
|
|
if (circuitToAddATo != null && circuitToAddBTo != null)
|
|
{
|
|
circuitToAddBTo.AddRange(circuitToAddATo);
|
|
circuits.Remove(circuitToAddATo);
|
|
return circuits;
|
|
}
|
|
|
|
if (circuitToAddATo != null)
|
|
{
|
|
circuitToAddATo.Add(a);
|
|
}
|
|
else
|
|
{
|
|
circuitToAddBTo!.Add(b);
|
|
}
|
|
|
|
return circuits;
|
|
}
|
|
|
|
private (Coordinate pointA, Coordinate pointB)[] GetAllCombinationsSortedByDistance(Coordinate[] coordinates)
|
|
{
|
|
var combinations = Combinations(coordinates)
|
|
.OrderBy(x => GetDistance(x.a, x.b))
|
|
.ToArray();
|
|
return combinations;
|
|
}
|
|
|
|
private IEnumerable<(TValue a, TValue b)> Combinations<TValue>(IEnumerable<TValue> values) where TValue:IComparable
|
|
{
|
|
var enumeratedValues = values.Index().ToArray();
|
|
var pairs =
|
|
from a in enumeratedValues
|
|
from b in enumeratedValues
|
|
where a.Index < b.Index
|
|
select (a.Item, b.Item);
|
|
return pairs;
|
|
}
|
|
} |