Add AoC 2025 project structure and first solutions

2025-12-04 21:40:42 +01:00
parent c83642d286
commit 1e98d90c33
15 changed files with 754 additions and 0 deletions
@@ -0,0 +1,112 @@
+using System;
+using System.IO;
+using System.Linq;
+using AdvenOfCode.Contracts;
+
+namespace AoC_2025;
+
+public class Day01 : IPuzzleSolver<int>
+{
+    private string[] ParsePuzzleInput(string path)
+    {
+        var puzzleInput = File.ReadAllLines(path)
+            .Where(l => !string.IsNullOrWhiteSpace(l))
+            .ToArray();
+        return puzzleInput;
+    }
+
+    public int SolvePart1(string pathToPuzzleInput)
+    {
+        var rotationInstructions = ParsePuzzleInput(pathToPuzzleInput);
+        var dialPosition = 50;
+        var timesZeroWasHit = 0;
+        foreach (var rotationAmount in rotationInstructions.Select(ParseRotationAmount))
+        {
+            dialPosition = (dialPosition + rotationAmount) % 100;
+            if (dialPosition == 0)
+                timesZeroWasHit++;
+        }
+        return timesZeroWasHit;
+    }
+    
+    public int SolvePart2(string pathToPuzzleInput)
+    {
+        var rotationInstructions = ParsePuzzleInput(pathToPuzzleInput);
+        var dialPosition = 50;
+        var timesZeroWasHit = 0;
+        foreach (var rotationAmount in rotationInstructions.Select(ParseRotationAmount))
+        {
+            var actualRotationAmount = 0;
+            if (rotationAmount < 0)
+            {
+                (var fullTurns, actualRotationAmount) = DivMod(rotationAmount, -100);
+                timesZeroWasHit += fullTurns;
+                if (dialPosition != 0 && dialPosition + actualRotationAmount <= 0)
+                    timesZeroWasHit++;
+            }
+            else
+            {
+                (var fullTurns, actualRotationAmount) = DivMod(rotationAmount, 100);
+                timesZeroWasHit += fullTurns;
+                if (dialPosition + actualRotationAmount >= 100)
+                    timesZeroWasHit++;
+            }
+
+            dialPosition = Mod(dialPosition + actualRotationAmount, 100);
+        }
+        return timesZeroWasHit;
+    }
+
+    private (int div, int mod) DivMod(int number, int divisor)
+    {
+        return (number / divisor, Mod(number, divisor));
+    }
+
+    private int Mod(int number, int divident)
+    {
+        var mod = number % divident;
+        if (number < 0 && divident > 0)
+        {
+            mod = divident + mod;
+        }
+
+        return mod;
+    }
+
+    private static bool HasPassedZero(bool hasOverflow, int dialPosition)
+    {
+        return dialPosition != 0 && hasOverflow;
+    }
+
+    private static (int nextDialPosition, bool passedZero) GetNextDialPosition(int rotationAmount, int dialPosition)
+    {
+        var actualRotation = rotationAmount % 100;
+        var nextDialPosition = dialPosition + actualRotation;
+        var hasOverflow = nextDialPosition is > 99 or < 1;
+        nextDialPosition %= 100;
+        if (nextDialPosition < 0)
+        {
+            nextDialPosition = 100 + nextDialPosition;
+        }
+        return (nextDialPosition, hasOverflow);
+    }
+
+    private static int ParseRotationAmount(string puzzleInput)
+    {
+        var direction = puzzleInput[..1];
+        var rotationAmount = int.Parse(puzzleInput[1..]);
+        if (direction == "L")
+        {
+            rotationAmount *= -1;
+        }
+
+        return rotationAmount;
+    }
+
+    private static int CountFullRotations(int rotationAmount)
+    {
+        var fullRotations = Math.Abs(rotationAmount / 100);
+
+        return fullRotations;
+    }
+}