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feat(2023-03): Finish day 3

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This commit is contained in:
Josh Creek
2023-12-04 17:39:37 +00:00
parent c5b096dbea
commit f068ba8b7b
1 changed files with 346 additions and 255 deletions
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AdventOfCode/AOC.Tests/Y2023/Day03.cs
+130 -39
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@@ -1,23 +1,23 @@
using System.Reflection;
namespace AOC.Tests.Y2023;
namespace AOC.Tests.Y2023
{
[TestFixture, Parallelizable(ParallelScope.All)]
[TestFixture]
[Parallelizable(ParallelScope.All)]
public class Day03
{
protected string GetThisClassName() { return this.GetType().Name; }
private string[] realData;
[SetUp]
public void Setup()
{
realData = File.ReadAllLines(Path.Combine(TestContext.CurrentContext.TestDirectory, "Y2023", "Data", $"{GetThisClassName()}.dat"));
realData = File.ReadAllLines(Path.Combine(TestContext.CurrentContext.TestDirectory, "Y2023", "Data",
$"{GetThisClassName()}.dat"));
}
protected string GetThisClassName() { return GetType().Name; }
private string[] realData;
private bool CheckSurroundingCellsForSymbols(char[,] grid, List<(int, int)> coords, bool isTesting = false)
{
char[,] grid2 = new char[grid.GetLength(0), grid.GetLength(1)];
foreach (var coord in coords)
foreach ((int, int) coord in coords)
{
int x = coord.Item1;
int y = coord.Item2;
@@ -63,9 +63,11 @@ namespace AOC.Tests.Y2023
{
line += grid2[i, j] != '\u0000' ? grid2[i, j] : '.';
}
Console.WriteLine(line);
}
}
return false;
}
@@ -123,7 +125,7 @@ namespace AOC.Tests.Y2023
// Check the eight surrounding cells of each digit in the number.
if (numberCoords.Count > 0)
{
bool isValidPartNumber = CheckSurroundingCellsForSymbols(grid, numberCoords, false);
bool isValidPartNumber = CheckSurroundingCellsForSymbols(grid, numberCoords);
// If any of the surrounding cells contain a symbol, add the number to a list.
if (isValidPartNumber)
{
@@ -140,15 +142,89 @@ namespace AOC.Tests.Y2023
return numbers;
}
public bool CheckSurroundingCellsForNumbers(char[,] grid, List<(int, int)> coords, bool isTesting = false)
private int CountNumbers(List<(int, int)> numberCoords)
{
foreach (var gearCoord in coords)
// Group coordinates by the X-axis and sort each group by the Y-axis
IEnumerable<IOrderedEnumerable<(int, int)>> groupedCoords = numberCoords.GroupBy(coord => coord.Item1)
.Select(group => group.OrderBy(coord => coord.Item2));
int numberCount = 0;
foreach (IOrderedEnumerable<(int, int)> group in groupedCoords)
{
int lastY = int.MinValue;
foreach ((int, int) coord in group)
{
// If there is a gap in the Y-axis, increment the number count
if (coord.Item2 - lastY > 1)
{
numberCount++;
}
lastY = coord.Item2;
}
}
return numberCount;
}
private List<int> ExtractNumbers(List<(int, int)> numberCoords, char[,] grid)
{
// Initialize a list to hold the extracted numbers
List<int> numbers = new();
// Sort the coordinates by Y-axis (Item2) then by X-axis (Item1)
List<(int, int)> sortedCoords =
numberCoords.OrderBy(coord => coord.Item2).ThenBy(coord => coord.Item1).ToList();
// Create a HashSet to keep track of processed coordinates
HashSet<(int, int)> processedCoords = new();
foreach ((int x, int y) in sortedCoords)
{
// Skip this coordinate if it has already been processed
if (processedCoords.Contains((x, y)))
{
continue;
}
// Start from the current coordinate and scan to the left until a non-digit is found or it reaches the beginning of the row
int startX = x;
while (startX > 0 && char.IsDigit(grid[startX - 1, y]))
{
startX--;
}
// Build the number by scanning to the right from the startX position
string currentNumberStr = "";
int currentX = startX;
while (currentX < grid.GetLength(0) && char.IsDigit(grid[currentX, y]))
{
currentNumberStr += grid[currentX, y];
// Mark the coordinate as processed
processedCoords.Add((currentX, y));
currentX++;
}
// If a number is formed, add it to the list
if (currentNumberStr.Length > 0)
{
numbers.Add(int.Parse(currentNumberStr));
}
}
// Return the list of extracted numbers
return numbers;
}
private int GetGearRatioFromExactlyTwoNumbersInSurroundingCells(char[,] grid, (int, int) gearCoord)
{
List<(int, int)> numberCoords = new();
int x = gearCoord.Item1;
int y = gearCoord.Item2;
int gearRatio = 0;
// Check the eight surrounding cells of each digit in the number.
// Check the eight surrounding cells of the gear
for (int i = x - 1; i <= x + 1; i++)
{
for (int j = y - 1; j <= y + 1; j++)
@@ -163,46 +239,59 @@ namespace AOC.Tests.Y2023
}
}
if (numberCoords.Count == 2)
// Consider each set of cells in the same x axis with a digit to their immediate right as a single number
foreach ((int, int) numberCoord in numberCoords)
{
int number1 = int.Parse(grid[numberCoords[0].Item1, numberCoords[0].Item2].ToString());
int number2 = int.Parse(grid[numberCoords[1].Item1, numberCoords[1].Item2].ToString());
int gearRatio = number1 * number2;
// gearRatios.Add(gearRatio);
Console.WriteLine($"{numberCoord.Item1},{numberCoord.Item2}");
}
Console.WriteLine("---");
List<int> numbers = ExtractNumbers(numberCoords, grid);
foreach (int number in numbers)
{
Console.WriteLine($"Number: {number}");
}
return false;
Console.WriteLine("===");
if (numbers.Count == 2)
{
// If there are exactly two numbers around the gear, generate the gear ratio
gearRatio = numbers[0] * numbers[1];
Console.WriteLine($"{numbers[0]} * {numbers[1]} = {gearRatio}");
}
return gearRatio;
}
private List<int> GetAllGearRatios(string[] lines)
private int GetSumOfAllGearRatios(string[] lines)
{
// Create a 2D array to represent the grid.
int rows = lines.Length;
int cols = lines[0].Length;
char[,] grid = new char[rows, cols];
int rows = lines.Length;
char[,] grid = new char[cols, rows];
// Populate the grid
for (int i = 0; i < rows; i++)
for (int j = 0; j < rows; j++)
{
string line = lines[i];
for (int j = 0; j < cols; j++)
string line = lines[j];
for (int i = 0; i < cols; i++)
{
grid[i, j] = line[j];
grid[i, j] = line[i];
}
}
List<int> gearRatios = new();
List<(int, int)> gearCoords = new();
// Iterate over each cell in the grid to find all gears
for (int i = 0; i < rows; i++)
for (int i = 0; i < cols; i++)
{
Console.WriteLine($"Line {i+1}");
for (int j = 0; j < cols; j++)
// Console.WriteLine($"Line {i + 1}");
for (int j = 0; j < rows; j++)
{
if (grid[i, j] == '*')
{
gearCoords.Add((i, j));
@@ -210,10 +299,13 @@ namespace AOC.Tests.Y2023
}
}
// Now find all instances where exactly two numbers are adjacent to a gear
int gearRatios = 0;
// Now find all instances where exactly two numbers are adjacent to a gear and sum their gear ratios
foreach ((int, int) gear in gearCoords)
{
gearRatios += GetGearRatioFromExactlyTwoNumbersInSurroundingCells(grid, gear);
}
// Return the list of numbers.
return gearRatios;
}
@@ -274,7 +366,7 @@ namespace AOC.Tests.Y2023
(9, 3),
(9, 5),
(9, 6),
(9,7),
(9, 7)
};
CheckSurroundingCellsForSymbols(grid, coords, true);
@@ -332,10 +424,10 @@ namespace AOC.Tests.Y2023
string[] lines = input != null ? input.Split("\n") : realData;
// A gear is any * symbol that is adjacent to exactly two part numbers. Its gear ratio is the result of multiplying those two numbers together.
List<int> gearRatios = GetAllGearRatios(lines);
int gearRatiosSum = GetSumOfAllGearRatios(lines);
// The result is the sum of all the gear ratios
int result = gearRatios.Sum();
int result = gearRatiosSum;
if (expected != null)
{
@@ -345,4 +437,3 @@ namespace AOC.Tests.Y2023
Console.WriteLine($"Part 2: {result}");
}
}
}