[2022] Day11 added

Year2022/Day11.cs

@@ -0,0 +1,171 @@
+using AdventOfCode.Utils.Extensions;
+
+namespace AdventOfCode.Year2022;
+
+public class Day11
+{
+    private static readonly List<Monkey> Part1Monkeys = new();
+    private static readonly List<Monkey> Part2Monkeys = new();
+
+    public Day11()
+    {
+        Console.WriteLine("Day11 Solution");
+        
+        File.ReadAllText("inputs/day11.txt").Split("\n\n").ToList().ForEach(monkey =>
+        {
+            string[] lines = monkey.Split("\n");
+            
+            // Getting starting items
+            List<Item> items1 = new List<Item>();
+            List<Item> items2 = new List<Item>();
+            lines[1][(lines[1].IndexOf(':') + 2)..].Split(", ").ToList().ForEach(item =>
+            {
+                items1.Add(new(Convert.ToInt32(item)));
+                items2.Add(new(Convert.ToInt32(item)));
+            });
+            
+            // Getting operation
+            string op = lines[2][19..];
+            
+            // Getting test info
+            int test = Convert.ToInt32(lines[3][21..]);
+            (int, int) testMonkeys = (Convert.ToInt32(lines[4][29..]), Convert.ToInt32(lines[5][30..]));
+
+            Part1Monkeys.Add(new Monkey(items1, op, test, testMonkeys));
+            Part2Monkeys.Add(new Monkey(items2, op, test, testMonkeys));
+        });
+        
+        Console.WriteLine($"Part1 Result: {Part1()}");
+        Console.WriteLine($"Part2 Result: {Part2()}");
+        Console.WriteLine("\n=============================\n");
+    }
+
+    private static ulong Part1()
+    {
+        ulong[] inspections = new ulong[Part1Monkeys.Count];
+        
+        for (int round = 0; round < 20; round++)
+            foreach (Monkey monkey in Part1Monkeys)
+            {
+                foreach (Item item in monkey.Items)
+                {
+                    if (monkey.Operation.Contains('+'))
+                        item.Value += Convert.ToInt32(monkey.Operation.Split(" ").Last());
+                    else if (monkey.Operation == "old * old")
+                        item.Value *= item.Value;
+                    else
+                        item.Value *= Convert.ToInt32(monkey.Operation.Split(" ").Last());
+                    item.Value /= 3;
+                    Part1Monkeys[
+                        item.Value % monkey.DivisionTest == 0
+                        ? monkey.TestMonkeys.Item1
+                        : monkey.TestMonkeys.Item2
+                    ].Items.Add(item);
+                    inspections[Part1Monkeys.IndexOf(monkey)]++;
+                }
+                monkey.Items.Clear();
+            }
+
+        return new List<ulong>(inspections).ProductOfMax(2);
+    }
+
+    private static ulong Part2()
+    {
+        for (double round = 0; round < 10000; round++)
+            foreach (var monkey in Part2Monkeys)
+            {
+                monkey.UpdateItems();
+                Dictionary<int, List<Item>> receiversAndItems = monkey.GetReceiversAndItems();
+                foreach (int key in receiversAndItems.Keys)
+                    Part2Monkeys[key].ReceiveItems(receiversAndItems[key]);
+            }
+        List<ulong> topMonkeys = new List<ulong>();
+        Part2Monkeys.ForEach(monkey => topMonkeys.Add((ulong) monkey.TotalItemsChecked));
+        return topMonkeys.ProductOfMax(2);
+    }
+
+    private class Monkey
+    {
+        public List<Item> Items { get; set; }
+        public string Operation { get; }
+        public int DivisionTest { get; }
+        public (int, int) TestMonkeys { get; }
+        public int TotalItemsChecked { get; private set; }
+
+        public Monkey(List<Item> items, string operation, int divisionTest, (int, int) testMonkeys)
+        {
+            Items = items;
+            Operation = operation;
+            DivisionTest = divisionTest;
+            TestMonkeys = testMonkeys;
+            TotalItemsChecked = 0;
+        }
+
+        public void UpdateItems()
+        {
+            if (Operation.Contains('+'))
+                foreach (Item item in Items)
+                    item.UpdateDivisibleBy(Operator.Add, Convert.ToInt32(Operation.Split(" ").Last()));
+            else if (Operation == "old * old")
+                foreach (Item item in Items)
+                    item.UpdateDivisibleBy(Operator.Square);
+            else
+                foreach (Item item in Items)
+                    item.UpdateDivisibleBy(Operator.Multiply, Convert.ToInt32(Operation.Split(" ").Last()));
+            TotalItemsChecked += Items.Count;
+        }
+
+        public Dictionary<int, List<Item>> GetReceiversAndItems()
+        {
+            Dictionary<int, List<Item>> result = new Dictionary<int, List<Item>>
+            {
+                [TestMonkeys.Item1] = new(),
+                [TestMonkeys.Item2] = new()
+            };
+            Items.ForEach(item =>
+            {
+                if (item.DivisibleBy[DivisionTest] == 0)
+                    result[TestMonkeys.Item1].Add(item);
+                else
+                    result[TestMonkeys.Item2].Add(item);
+            });
+            Items = new List<Item>();
+            return result;
+        }
+
+        public void ReceiveItems(List<Item> items)
+        {
+            Items.AddRange(items);
+        }
+    }
+
+    private class Item
+    {
+        public int Value { get; set; }
+        public Dictionary<int, int> DivisibleBy { get; } = new();
+
+        public Item(int value)
+        {
+            Value = value;
+            foreach (int i in new[] { 2, 3, 5, 7, 11, 13, 17, 19, 23 })
+                DivisibleBy.Add(i, value % i);
+        }
+
+        public void UpdateDivisibleBy(Operator op, int value = default)
+        {
+            foreach (int key in DivisibleBy.Keys)
+                DivisibleBy[key] = op switch
+                {
+                    Operator.Add => (DivisibleBy[key] + value) % key,
+                    Operator.Multiply => DivisibleBy[key] * value % key,
+                    Operator.Square => DivisibleBy[key] * DivisibleBy[key] % key,
+                    _ => throw new ArgumentOutOfRangeException(nameof(op), op, null)
+                };
+        }
+    }
+
+    private enum Operator
+    {
+        Add, Multiply, Square
+    }
+}

Year2022/Loader2022.cs

@@ -4,6 +4,12 @@ public static class Loader2022
 {
     public static void Load()
     {
+        /* Year 2022
+         *
+         * Solutions in C# for the 2022 Advent of Code
+         * Slower solutions are commented
+         */
+        
         new Day1();
         new Day2();
         new Day3();
@@ -11,8 +17,9 @@ public static class Loader2022
         new Day5();
         new Day6();
         new Day7();
-        // new Day8();  -- Commented because it's a slow solution
+        // new Day8();  
         new Day9();
         new Day10();
+        // new Day11();
     }
 }