Add day 11 part 1

2022-12-14 13:39:01 +01:00
parent fe91c0f07a
commit a985d2e00c
1 changed files with 204 additions and 0 deletions
--- a/Days/Day11.cs
+++ b/Days/Day11.cs
@@ -0,0 +1,204 @@
+using System.Collections.Immutable;
+using Spectre.Console;
+
+namespace AdventOfCode.Days;
+
+public class Monkey
+{
+    public int Number { get; }
+    public int InspectionCount { get; private set; }
+
+    private readonly Queue<int> _items;
+    private readonly Func<int, int> _operation;
+    private readonly int _testDivider;
+    private readonly int _testFailMonkey;
+    private readonly int _testSuccessMonkey;
+
+    public Monkey(int number, IEnumerable<int> items, Func<int, int> operation, int testDivider, int testFailMonkey, int testSuccessMonkey)
+    {
+        Number = number;
+        _operation = operation;
+        _testDivider = testDivider;
+        _testFailMonkey = testFailMonkey;
+        _testSuccessMonkey = testSuccessMonkey;
+
+        InspectionCount = 0;
+        _items = new Queue<int>(items);
+    }
+
+    public void AddItem(int item)
+    {
+        _items.Enqueue(item);
+    }
+
+    public bool ThrowItem(IImmutableList<Monkey> monkeys)
+    {
+        // Return false if there's no item to throw
+        if (_items.Count < 1)
+        {
+            return false;
+        }
+
+        // Increment inspection count
+        InspectionCount++;
+
+        // Take next item to throw
+        var item = _items.Dequeue();
+
+        // Apply the operation on worry level
+        var newValue = _operation(item);
+
+        // Divide worry level by 3 before test
+        newValue = newValue / 3;
+
+        // Test is a success
+        if (newValue % _testDivider == 0)
+        {
+            monkeys[_testSuccessMonkey].AddItem(newValue);
+        }
+        // Test is a fail
+        else
+        {
+            monkeys[_testFailMonkey].AddItem(newValue);
+        }
+
+        return true;
+    }
+}
+
+public class Day11 : Day
+{
+    public override int Number => 11;
+    public override string Name => "Monkey in the Middle";
+    public override void RunPart1()
+    {
+        const int roundsCount = 20;
+
+        var monkeys = ParseMonkeys();
+
+        // Do 20 rounds
+        for (int round = 0; round < roundsCount; round++)
+        {
+            foreach (var monkey in monkeys)
+            {
+                // Throw items while there's some
+                while (monkey.ThrowItem(monkeys)) { }
+            }
+        }
+
+        var topMonkeys = monkeys.OrderByDescending(m => m.InspectionCount).Take(2).ToList();
+
+        AnsiConsole.MarkupLine($"[green]Monkey business: [yellow]{topMonkeys[0].InspectionCount * topMonkeys[1].InspectionCount}[/][/]");
+    }
+
+    public override void RunPart2()
+    {
+        throw new NotImplementedException();
+    }
+
+    private static IImmutableList<Monkey> ParseMonkeys()
+    {
+        var monkeys = new List<Monkey>();
+
+        // Split by monkey description
+        foreach (var monkey in Input.ReplaceLineEndings("\n").Split("\n\n"))
+        {
+            var split = monkey.Split('\n');
+            var numberLine = split[0];
+            var itemsLine = split[1];
+            var operationLine = split[2];
+            var testDividerLine = split[3];
+            var testSuccessLine = split[4];
+            var testFailLine = split[5];
+
+            // Monkey attributes
+            var number = int.Parse(numberLine[numberLine.LastIndexOf(' ')..^1]);
+            var items = itemsLine[(itemsLine.IndexOf(':') + 2)..].Split(", ").Select(int.Parse);
+
+            // Read operation
+            operationLine = operationLine[(operationLine.IndexOf('=') + 2)..];
+            int? rightOperand = operationLine.EndsWith("old") ? null : int.Parse(operationLine.Split('+', '*')[1].Trim());
+
+            Func<int, int> operation = operationLine.Contains('+') switch
+            {
+                true => rightOperand is null
+                    ? old => old + old
+                    : old => old + (int)rightOperand,
+                false => rightOperand is null
+                    ? old => old * old
+                    : old => old * (int)rightOperand
+            };
+
+            var testDivider = int.Parse(testDividerLine[testDividerLine.LastIndexOf(' ')..]);
+            var testSuccessMonkey = int.Parse(testSuccessLine[testSuccessLine.LastIndexOf(' ')..]);
+            var testFailMonkey = int.Parse(testFailLine[testFailLine.LastIndexOf(' ')..]);
+
+            monkeys.Add(new Monkey(number, items, operation, testDivider, testFailMonkey, testSuccessMonkey));
+        }
+
+        return monkeys.ToImmutableList();
+    }
+
+    #region Input
+
+    public const string Input =
+    """
+    Monkey 0:
+      Starting items: 89, 95, 92, 64, 87, 68
+      Operation: new = old * 11
+      Test: divisible by 2
+        If true: throw to monkey 7
+        If false: throw to monkey 4
+
+    Monkey 1:
+      Starting items: 87, 67
+      Operation: new = old + 1
+      Test: divisible by 13
+        If true: throw to monkey 3
+        If false: throw to monkey 6
+
+    Monkey 2:
+      Starting items: 95, 79, 92, 82, 60
+      Operation: new = old + 6
+      Test: divisible by 3
+        If true: throw to monkey 1
+        If false: throw to monkey 6
+
+    Monkey 3:
+      Starting items: 67, 97, 56
+      Operation: new = old * old
+      Test: divisible by 17
+        If true: throw to monkey 7
+        If false: throw to monkey 0
+
+    Monkey 4:
+      Starting items: 80, 68, 87, 94, 61, 59, 50, 68
+      Operation: new = old * 7
+      Test: divisible by 19
+        If true: throw to monkey 5
+        If false: throw to monkey 2
+
+    Monkey 5:
+      Starting items: 73, 51, 76, 59
+      Operation: new = old + 8
+      Test: divisible by 7
+        If true: throw to monkey 2
+        If false: throw to monkey 1
+
+    Monkey 6:
+      Starting items: 92
+      Operation: new = old + 5
+      Test: divisible by 11
+        If true: throw to monkey 3
+        If false: throw to monkey 0
+
+    Monkey 7:
+      Starting items: 99, 76, 78, 76, 79, 90, 89
+      Operation: new = old + 7
+      Test: divisible by 5
+        If true: throw to monkey 4
+        If false: throw to monkey 5
+    """;
+
+    #endregion
+}