AdventOfCode/AoC_2025/Day12.cs

44 lines
1.6 KiB
C#

using AdvenOfCode.Contracts;
namespace AoC_2025;
public class Day12 : IPuzzleSolver<long>
{
private (int[] presentSizes, (int area, int[] presentCounts)[] regions) ParsePuzzleInput(string path)
{
var puzzleInput = File.ReadAllText(path)
.Split($"{Environment.NewLine}{Environment.NewLine}", StringSplitOptions.TrimEntries)
.ToList();
var presentSizes = puzzleInput[..^1]
.Select(s => s.Count(c => c == '#'))
.ToArray();
var regions = puzzleInput[^1]
.Split(Environment.NewLine, StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
.Select(s => s.Split(':', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
.Select(s =>
(s[0].Split('x').Select(int.Parse).Aggregate((x, y) => x * y),
s[1].Split(' ').Select(int.Parse).ToArray()))
.ToArray();
return (presentSizes, regions);
}
public long SolvePart1(string pathToPuzzleInput)
{
var (presentSizes, regions) = ParsePuzzleInput(pathToPuzzleInput);
var everythingFits =
regions.Count(region => region.area >= GetMinTotalPresentArea(region.presentCounts, presentSizes));
return everythingFits;
}
private int GetMinTotalPresentArea(int[] presentCounts, int[] presentSizes)
{
return presentCounts
.Zip(presentSizes, (count, size) => count * size)
.Sum();
}
public long SolvePart2(string pathToPuzzleInput)
{
return 0;
}
}