Merge pull request #32 from MartinZikmund/feature/aoc2025-day6

Author: MartinZikmund

src/AdventOfCode.Puzzles/2025/06/Part1/AoC2025Day6Part1.cs

@@ -0,0 +1,39 @@
+
+namespace AdventOfCode.Puzzles._2025._06.Part1;
+
+public class AoC2025Day6Part1 : IPuzzleSolution
+{
+    public async Task<string> SolveAsync(StreamReader inputReader)
+    {
+        var problems = new List<string[]>();
+        var lines = await inputReader.ReadAllLinesAsync();
+        foreach (var line in lines)
+        {
+            var parts = line.Split(' ', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+            problems.Add(parts);
+        }
+
+        ulong total = 0;
+        for (int i = 0; i < problems[0].Length; i++)
+        {
+            var multiply = problems[problems.Count - 1][i] == "*";
+            var currentResult = multiply ? 1UL : 0;
+            for (int line = 0; line < problems.Count - 1; line++)
+            {
+                var number = ulong.Parse(problems[line][i]);
+                if (multiply)
+                {
+                    currentResult *= number;
+                }
+                else
+                {
+                    currentResult += number;
+                }
+            }
+
+            total += currentResult;
+        }
+
+        return total.ToString();
+    }
+}

src/AdventOfCode.Puzzles/2025/06/Part2/AoC2025Day6Part2.cs

@@ -0,0 +1,54 @@
+namespace AdventOfCode.Puzzles._2025._06.Part2;
+
+public class AoC2025Day6Part2 : IPuzzleSolution
+{
+    public async Task<string> SolveAsync(StreamReader inputReader)
+    {
+        var problems = new List<string[]>();
+        var lines = await inputReader.ReadAllLinesAsync();
+        
+        var operatorsLine = lines[lines.Count - 1];
+        ulong gradTotal = 0;
+
+        var startIndex = 0;
+        do
+        {
+            var multiply = operatorsLine[startIndex] == '*';
+            ulong currentTotal = multiply ? 1UL : 0; 
+
+            var endIndex = operatorsLine.IndexOfAny(new[] { '+', '*' }, startIndex + 1);
+            if (endIndex == -1)
+            {
+                endIndex = operatorsLine.Length + 1;
+            }
+
+            for (var currentColumn = endIndex - 2; currentColumn >= startIndex; currentColumn--)
+            {
+                var currentNumber = 0UL;
+                for (var currentRow = 0; currentRow < lines.Count - 1; currentRow++)
+                {
+                    var character = lines[currentRow][currentColumn];
+                    if (char.IsDigit(character))
+                    {
+                        var number = (ulong)(character - '0');
+                        currentNumber *= 10;
+                        currentNumber += number;
+                    }
+                }
+
+                if (multiply)
+                {
+                    currentTotal *= currentNumber;
+                }
+                else
+                {
+                    currentTotal += currentNumber;
+                }
+            }
+            gradTotal += currentTotal;
+            startIndex = endIndex;
+        } while (startIndex < operatorsLine.Length);
+
+        return gradTotal.ToString();
+    }
+}

src/AdventOfCode.Puzzles/2025/06/TestData.txt

@@ -0,0 +1,4 @@
+123 328  51 64 
+ 45 64  387 23 
+  6 98  215 314
+*   +   *   +