From 18affcc67ad32eeaa2be96b2ec2ce81791019048 Mon Sep 17 00:00:00 2001
From: Alexander Sigler <asigler@costar.com>
Date: Thu, 9 Dec 2021 17:07:11 -0800
Subject: [PATCH] Finished Day 4 and added it to test

---
 AOC2021.Test/AOC2021.Test.csproj              |   6 +
 AOC2021.Test/DayTest.cs                       |   8 +
 AOC2021.Test/Input/Day4_input.txt             | 601 ++++++++++++++++++
 AOC2021.Test/Input/Day4_test.txt              |  19 +
 AOC2021/Controllers/AdventOfCodeController.cs |   1 +
 AOC2021/Days/Day4.cs                          |  86 +++
 AOC2021/Models/Day4/BingoBoard.cs             | 104 +++
 AOC2021/Models/Day4/BingoSpot.cs              |  10 +
 8 files changed, 835 insertions(+)
 create mode 100644 AOC2021.Test/Input/Day4_input.txt
 create mode 100644 AOC2021.Test/Input/Day4_test.txt
 create mode 100644 AOC2021/Days/Day4.cs
 create mode 100644 AOC2021/Models/Day4/BingoBoard.cs
 create mode 100644 AOC2021/Models/Day4/BingoSpot.cs

diff --git a/AOC2021.Test/AOC2021.Test.csproj b/AOC2021.Test/AOC2021.Test.csproj
index 077343f..0e8762c 100644
--- a/AOC2021.Test/AOC2021.Test.csproj
+++ b/AOC2021.Test/AOC2021.Test.csproj
@@ -36,6 +36,12 @@
     <None Update="Input\Day3_test.txt">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>
+    <None Update="Input\Day4_input.txt">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
+    <None Update="Input\Day4_test.txt">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
   </ItemGroup>
 
 </Project>
diff --git a/AOC2021.Test/DayTest.cs b/AOC2021.Test/DayTest.cs
index 8b1aef5..a4ab03c 100644
--- a/AOC2021.Test/DayTest.cs
+++ b/AOC2021.Test/DayTest.cs
@@ -38,5 +38,13 @@ namespace AOC2021.Tests
             var result = _tester.Test(request);
             Assert.IsTrue(request.Answer.Equals(result.Answer));
         }
+
+        [TestMethod]
+        public void Day4()
+        {
+            var request = new TestRequest() { Day = "day4", Answer = new Answer() { Day_A_Test = "4512", Day_A_Input = "63424", Day_B_Test = "1924", Day_B_Input = "23541" } };
+            var result = _tester.Test(request);
+            Assert.IsTrue(request.Answer.Equals(result.Answer));
+        }
     }
 }
diff --git a/AOC2021.Test/Input/Day4_input.txt b/AOC2021.Test/Input/Day4_input.txt
new file mode 100644
index 0000000..9c7ad40
--- /dev/null
+++ b/AOC2021.Test/Input/Day4_input.txt
@@ -0,0 +1,601 @@
+63,23,2,65,55,94,38,20,22,39,5,98,9,60,80,45,99,68,12,3,6,34,64,10,70,69,95,96,83,81,32,30,42,73,52,48,92,28,37,35,54,7,50,21,74,36,91,97,13,71,86,53,46,58,76,77,14,88,78,1,33,51,89,26,27,31,82,44,61,62,75,66,11,93,49,43,85,0,87,40,24,29,15,59,16,67,19,72,57,41,8,79,56,4,18,17,84,90,47,25
+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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\ No newline at end of file
diff --git a/AOC2021.Test/Input/Day4_test.txt b/AOC2021.Test/Input/Day4_test.txt
new file mode 100644
index 0000000..cabc5cc
--- /dev/null
+++ b/AOC2021.Test/Input/Day4_test.txt
@@ -0,0 +1,19 @@
+7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
+
+22 13 17 11  0
+ 8  2 23  4 24
+21  9 14 16  7
+ 6 10  3 18  5
+ 1 12 20 15 19
+
+ 3 15  0  2 22
+ 9 18 13 17  5
+19  8  7 25 23
+20 11 10 24  4
+14 21 16 12  6
+
+14 21 17 24  4
+10 16 15  9 19
+18  8 23 26 20
+22 11 13  6  5
+ 2  0 12  3  7
\ No newline at end of file
diff --git a/AOC2021/Controllers/AdventOfCodeController.cs b/AOC2021/Controllers/AdventOfCodeController.cs
index 5e66724..e08ab44 100644
--- a/AOC2021/Controllers/AdventOfCodeController.cs
+++ b/AOC2021/Controllers/AdventOfCodeController.cs
@@ -22,6 +22,7 @@ namespace AOC2021.Controllers
         [Route("day1")]
         [Route("day2")]
         [Route("day3")]
+        [Route("day4")]
         public AOCResponse Day(AOCVersion version, [FromBody] string input, bool IgnoreLogMessages = false)
         {
             AOCRequest request = new AOCRequest() { Input = input, Version = version, IgnoreLogMessages = IgnoreLogMessages };
diff --git a/AOC2021/Days/Day4.cs b/AOC2021/Days/Day4.cs
new file mode 100644
index 0000000..7757fb7
--- /dev/null
+++ b/AOC2021/Days/Day4.cs
@@ -0,0 +1,86 @@
+using AOC2021.Helper;
+using AOC2021.Models;
+using AOC2021.Models.Day4;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace AOC2021.Days
+{
+    public class Day4 : AOCDay
+    {
+        private static readonly int BOARD_SIZE = 5;
+        private List<BingoBoard> _boards;
+        public Day4()
+        {
+            _boards = new List<BingoBoard>();
+        }
+        protected override AOCResponse ExecutePartA()
+        {
+            var input = GetSplitInput();
+            var checkedValues = input.First().Trim().Split(","); //Save selected answers into variable
+            CreateBoards(input);
+
+            BingoBoard winner = null;
+            foreach (var ball in checkedValues)
+            {
+                Log("Ball picked was " + ball);
+                foreach (var board in _boards)
+                {
+                    board.MarkValueAsChecked(ball.ToInt());
+                    if (board.IsWinner())
+                    {
+                        winner = board;
+                        Log("We have a winning board, number " + winner.Id);
+                        break;
+                    }
+                }
+                if (winner != null)
+                    break;
+            }
+            this._response.Answer = winner.CalculateScore().ToString();
+            Log("Winning board score is " + this._response.Answer);
+
+            return this._response;
+        }
+
+        protected override AOCResponse ExecutePartB()
+        {
+            var input = GetSplitInput();
+            var checkedValues = input.First().Trim().Split(","); //Save selected answers into variable
+            CreateBoards(input);
+
+            BingoBoard winner = null;
+            foreach (var ball in checkedValues)
+            {
+                Log("Ball picked was " + ball);
+                foreach (var board in _boards.Reverse<BingoBoard>())
+                {
+                    board.MarkValueAsChecked(ball.ToInt());
+                    if (board.IsWinner())
+                    {
+                        winner = board;
+                        _boards.Remove(board);
+                    }
+                }
+            }
+            this._response.Answer = winner.CalculateScore().ToString();
+            Log("Winning board score is " + this._response.Answer);
+            return this._response;
+        }
+
+        private void CreateBoards(string[] input)
+        {
+            //Create all of our game boards
+            int skipValue = 2;
+            while (skipValue < input.Length)
+            {
+                var group = input.Skip(skipValue).Take(5);
+                _boards.Add(new BingoBoard(BOARD_SIZE, group));
+                skipValue += 6;
+            }
+
+        }
+    }
+}
diff --git a/AOC2021/Models/Day4/BingoBoard.cs b/AOC2021/Models/Day4/BingoBoard.cs
new file mode 100644
index 0000000..28710dd
--- /dev/null
+++ b/AOC2021/Models/Day4/BingoBoard.cs
@@ -0,0 +1,104 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace AOC2021.Models.Day4
+{
+    public class BingoBoard
+    {
+        private static int ID_COUNT = 1;
+        public int Id;
+        private int _size;
+        private List<BingoSpot> _board;
+        private int _lastAnswer;
+        public BingoBoard(int size, IEnumerable<string> values)
+        {
+            Id = ID_COUNT++;
+            _size = size;
+            _board = new List<BingoSpot>();
+            ConstructBoard(values);
+        }
+
+        private void ConstructBoard(IEnumerable<string> values)
+        {
+            for (int x = 0; x < values.Count(); x++)
+            {
+                var splitValue = values.ElementAt(x).Trim().Replace("  ", " ").Split(" ");
+                for (int y = 0; y < splitValue.Length; y++)
+                {
+                    _board.Add(new BingoSpot()
+                    {
+                        Checked = false,
+                        Value = Convert.ToInt32(splitValue[y]),
+                        X = x,
+                        Y = y
+                    });
+                }
+            }
+        }
+
+        private BingoSpot SpotAt(int x, int y)
+        {
+            foreach (var bs in _board)
+                if (bs.X == x && bs.Y == y)
+                    return bs;
+            throw new Exception($"Can't find spot {x},{y} in the bingo board!");
+        }
+
+        public void MarkValueAsChecked(int value)
+        {
+
+            foreach (var bs in _board)
+                if (bs.Value == value)
+                {
+                    bs.Checked = true;
+                }
+            _lastAnswer = value;
+        }
+
+        public string PrintBoard()
+        {
+            var boardPrintout = string.Empty;
+            for (int x = 0; x < _size; x++)
+            {
+                var line = string.Empty;
+                for (int y = 0; y < _size; y++)
+                {
+                    line += $"{SpotAt(x, y).Value} ";
+                }
+                boardPrintout += $"{line}{Environment.NewLine}";
+            }
+            return boardPrintout;
+        }
+
+        public bool IsWinner()
+        {
+            for (int x = 0; x < _size; x++)
+            {
+                //If its still checked, and the next spot is NOT checked set to false and ends the check
+                bool horizontalRow = true;
+                bool verticalRow = true;
+                for (int y = 0; y < _size; y++)
+                {
+                    if (horizontalRow && !SpotAt(x, y).Checked)
+                        horizontalRow = false;
+                    if (verticalRow && !SpotAt(y, x).Checked)
+                        verticalRow = false;
+                }
+                if (horizontalRow || verticalRow)
+                    return true;
+            }
+            return false;
+        }
+
+        public int CalculateScore()
+        {
+            int unMarked = 0;
+            foreach (var x in _board)
+                if (!x.Checked)
+                    unMarked += x.Value;
+            return unMarked * _lastAnswer;
+        }
+    }
+}
diff --git a/AOC2021/Models/Day4/BingoSpot.cs b/AOC2021/Models/Day4/BingoSpot.cs
new file mode 100644
index 0000000..e2b03f2
--- /dev/null
+++ b/AOC2021/Models/Day4/BingoSpot.cs
@@ -0,0 +1,10 @@
+namespace AOC2021.Models.Day4
+{
+    public class BingoSpot
+    {
+        public int Value { get; set; }
+        public int X { get; set; }
+        public int Y { get; set; }
+        public bool Checked { get; set; }
+    }
+}