Initial Commit

2024/Day02CSharp/Program.cs

@@ -0,0 +1,141 @@
+Day02Parsed exParsed = new Day02Parsed("example-input.txt");
+
+Console.WriteLine("Example Part01: {0}", exParsed.GetSafeReportCount01());
+Console.WriteLine("Example Part02: {0}", exParsed.GetSafeReportCount02());
+
+Day02Parsed pzParsed = new Day02Parsed("puzzle-input.txt");
+
+Console.WriteLine("Puzzle Part01: {0}", pzParsed.GetSafeReportCount01());
+Console.WriteLine("Puzzle Part02: {0}", pzParsed.GetSafeReportCount02());
+
+class Day02Parsed : AdventCommon.ParsedInput
+{
+    List<List<int>> Reports = new List<List<int>>();
+
+    public Day02Parsed(string fileName) : base(fileName)
+    {
+        
+    }
+
+    public int GetSafeReportCount01()
+    {
+        int count = 0;
+
+        for (int i = 0; i < Reports.Count; i++)
+        {
+            if (IsSafe(Reports[i]))
+            {
+                count++;
+            }
+        }
+
+        return count;
+    }
+
+    public int GetSafeReportCount02()
+    {
+        int count = 0;
+
+        for (int i = 0; i < Reports.Count; i++)
+        {
+            // First see if its safe outright
+            if (IsSafe(Reports[i]))
+            {
+                count++;
+            }
+            else 
+            {
+                // Remove one start to end and check again
+                for (int j = 0; j < Reports[i].Count; j++)
+                {
+                    List<int> newReport = new List<int>(Reports[i]);
+                    newReport.RemoveAt(j);
+                    if (IsSafe(newReport))
+                    {
+                        count++;
+                        break;
+                    }
+                }
+            }
+        }
+
+        return count;
+    }
+
+    public bool IsSafe(List<int> report)
+    {
+        bool isAscending = false;
+
+        if ( report[0] < report[1] )
+        {
+            isAscending = true;
+        }
+
+        {
+            int rightDiff = report[1] - report[0];
+
+            if (Math.Abs(rightDiff) < 1 || Math.Abs(rightDiff) > 3)
+            {
+                return false;
+            }
+        }
+
+        for (int i = 1; i < report.Count - 1; i++)
+        {
+            int leftDiff = report[i] - report[i - 1];
+            int rightDiff = report[i + 1] - report[i];
+
+            // if ascending and either difference is negative, not safe
+            if (isAscending && (leftDiff < 0 || rightDiff < 0))
+            {
+                return false;
+            }
+            // if descending and either difference is positive, not safe
+            else if (!isAscending && (rightDiff > 0 || leftDiff > 0))
+            {
+                return false;
+            }
+
+            if (Math.Abs(leftDiff) < 1 || Math.Abs(leftDiff) > 3)
+            {
+                return false;
+            }
+
+            if (Math.Abs(rightDiff) < 1 || Math.Abs(rightDiff) > 3)
+            {
+                return false;
+            }
+        }
+
+        {
+            int leftDiff = report[report.Count - 1] - report[report.Count - 2];
+            if (isAscending && leftDiff < 0)
+            {
+                return false;
+            }
+
+            if (Math.Abs(leftDiff) < 1 || Math.Abs(leftDiff) > 3)
+            {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+
+    public override bool ParseLine(string line, object? context = null)
+    {
+        List<int> levels = new List<int>();
+        var split = line.Split(' ', StringSplitOptions.RemoveEmptyEntries);
+
+        foreach (var level in split)
+        {
+            levels.Add(Int32.Parse(level));
+        }
+
+        Reports.Add(levels);
+
+        return true;
+    }
+}