I am trying to make the tic tac toe game in C# Windows Forms using the minimax algorithm as the opponent. So instead of making the best move, like preventing the player from winning or playing a move that allows it to get closer to winning, it moves to the following empty index on the board. So how could I fix the algorithm?
int evaluate(int[] grid)
{
for(int i = 0; i < 9; i += 3)
{
if (grid[i] == 0) continue;
if (grid[i] == grid[i + 1] && grid [i] == grid[i + 2])
return grid[i]==1 ? 10 :-10;
}
for (int i = 0; i < 3; i++)
{
if (grid[i] == 0) continue;
if (grid[i] == grid[i + 3] && grid[i] == grid[i + 6])
return grid[i] == 1 ? 10 : -10;
}
if ((grid[0] == grid[4] && grid[4] == grid[8]) || (grid[2] == grid[4] && grid[4] == grid[6]))
return grid[4] == 1 ? 10 : -10;
return 0;
}
bool isMovesLeft(int[] grid)
{
for(int i = 0; i< grid.Length; i++)
{
if (grid[i] == 0) return true;
}
return false;
}
int miniMax(int[] grid,int depth, bool isMax)
{
int isWon = evaluate(grid);
if (isWon == 10 || isWon == -10)
return isWon;
if(!isMovesLeft(grid))
return 0;
if (isMax)
{
int best = int.MinValue;
for(int i = 0;i< grid.Length;i++)
{
if (grid[i] == 0)
{
grid[i] = 1;
best = Math.Max(best,miniMax(grid, depth+1, !isMax));
grid[i] = 0;
}
}
return best;
}
else
{
int best = int.MaxValue;
for (int i = 0; i < grid.Length; i++)
{
if (grid[i] == 0)
{
grid[i] = 2;
best = Math.Min(best, miniMax(grid, depth+1, !isMax));
grid[i] = 0;
}
}
return best;
}
}
void moveByAI()
{
int best = int.MinValue;
int move = -1;
for(int i =0; i<9;i++)
{
if (grids[i]==0)
{
grids[i] = 2;
int locValue = miniMax(grids, 0, true);
grids[i] = 0;
if(locValue > best)
{
move = i;
best = locValue;
MessageBox.Show(""+i);
}
}
}
buttons[move].PerformClick();
}
I am working on an A* Pathfinding method that uses a custom class instead of nodes, but am having issues with my loops. The first for loop using int i is able to go up to 3 (Player1.instance.movement = 3), but I need to use an if statement inside of that loop to check if the target position has already been found. I am wondering if it is possible to break my for loop when my If statement is false.
public void GetNeighbors(Tile originTile)
{
Tile originalTile = originTile;
nextTile.Clear();
int minX = 0;
int minY = 0;
var originCostFunc = Mathf.Infinity;
for (int i = 0; i < Player1.instance.movement; i++)
{
for (int x = -1; x <= 1; x++)
{
for (int y = -1; y <= 1; y++)
{
if (x != y && y != x)
{
var costX = Mathf.Abs((originTile.transform.position.x + x) - originalTile.transform.position.x);
var costY = Mathf.Abs((originTile.transform.position.y + y) - originalTile.transform.position.y);
var distanceX = Mathf.Abs(targetPos.transform.position.x - (originTile.transform.position.x + x));
var distanceY = Mathf.Abs(targetPos.transform.position.y - (originTile.transform.position.y + y));
var costFunc = costX + costY + distanceX + distanceY;
if (costFunc <= originCostFunc)
{
originCostFunc = costFunc;
minX = x;
minY = y;
Debug.Log($"x: {x}, y: {y}");
}
}
}
}
nextTile.Add(GridManagerHandPlaced.instance.GetTileAtPosition(new Vector2(originTile.transform.position.x + minX, originTile.transform.position.y + minY)));
if (nextTile[i] != targetPos)
{
originTile = nextTile[i];
}
else
{
break;
}
}
DisplayPath();
}
You can break loop several times by condition.
bool breakLoop = false;
for (int i = 0; i < length; i++)
{
for (int j = 0; j < length; j++)
{
for (int k = 0; k < length; k++)
{
breakLoop = nextTile == target;
if (breakLoop)
break;
}
if (breakLoop)
break;
}
if (breakLoop)
break;
}
Or move search logic to separated method and return a value from any number of nested loops
string path = FindPath();
Display(path);
string FindPath()
{
for (int i = 0; i < length; i++)
{
for (int j = 0; j < length; j++)
{
for (int k = 0; k < length; k++)
{
if (nextTile == target)
return nextTile;
}
}
}
return null;
}
Never use goto operator.
This is one of the few valid cases where I'd use goto. In-fact, this is the example given in the docs for when it should be used.
void CheckMatrices(Dictionary<string, int[][]> matrixLookup, int target)
{
foreach (var (key, matrix) in matrixLookup)
{
for (int row = 0; row < matrix.Length; row++)
{
for (int col = 0; col < matrix[row].Length; col++)
{
if (matrix[row][col] == target)
{
goto Found;
}
}
}
Console.WriteLine($"Not found {target} in matrix {key}.");
continue;
Found:
Console.WriteLine($"Found {target} in matrix {key}.");
}
}
Note the syntax for the label is simply myLabel: and you can place it anywhere in procedurally executable code.
For sake of covering other ways of handling this situation, here is the boolean solution.
bool breakLoops = false;
for (int i = 0; i < length1; i++)
{
for (int ii = 0; ii < length2; ii++)
{
for (int iii = 0; iii < length3; iii++)
{
if (breakingCondition)
{
breakLoops = true;
break;
}
}
if (breakLoops) break;
}
if (breakLoops) break;
}
Simple and straightforward, but requires a break condition check at the end of each loop that you want to break out of.
I am having trouble editing the values of a 2d char array.
char[,] chrRaster = new char[4, 5];
After adding values to the array and printing it to the console, I get:
// Input example:
*****
**.**
*****
****.
I am trying to make an algorithm that replaces every '*' that is beside, under or above a '.' by a '.' and then printing this to the console.
// Output after algorithm example:
**.**
*...*
**.*.
***..
I have tried converting the 2d char array to a 2d string array and then using IndexOf('*') to replace every '*' that is beside, under or above a '.', and I also tried calculating this using a number of if and for loops without any luck.
static void Main(string[] args)
{
// Variablen
int intTestgeval = 0; // Number of times you want program to repeat
int intN = 0; // Number of rows
int intM = 0; // Number of coloms
char chrGrond; // Used to store '*' or '.'
char[,] chrRaster; // 2d char array used to store all values
// Code
try
{
intTestgeval = Int32.Parse(Console.ReadLine()); // Number of times program will repeat
if(intTestgeval > 150) // Program can not repeat more then 150 times
{
throw new Exception();
}
}
catch (Exception)
{
Environment.Exit(0);
}
intN = Controle(intN); // Number of rows ophalen
intM = Controle(intM); // Number of Coloms ophalen
chrRaster = new char[intN, intM]; // Initializing array with user input
for (int intR = 0; intR < intTestgeval; intR++) // Print 2d array to console
{
for(int intY = 0; intY < intN; intY++)
{
for(int intZ = 0; intZ < intM; intZ++)
{
chrGrond = Convert.ToChar(Console.ReadKey().KeyChar);
chrRaster[intY, intZ] = chrGrond;
}
Console.WriteLine();
}
instorten[intR] = Instorten(chrRaster, intN, intM); // Ignore this part, that's another part of my assignment not related to my question.
}
}
static int Controle( int intX )
{
try
{
intX = Int32.Parse(Console.ReadLine());
if (intX > 150 || intX < 1) // Length of row and colom can not exceed 20 and can not go lower then 1
{
throw new Exception();
}
return intX;
}
catch // Program will off if value does not meet requirements
{
Environment.Exit(0);
return intX;
}
}
// It is this part of the program I need help with. This is what I tried but can't get any further
static int Instorten(char[,] chrRaster, int intN, int intM)
{
for (int intY = 0; intY < intN; intY++)
{
for (int intZ = 0; intZ < intM; intZ++)
{
if(chrRaster[intY, intZ] == '.' && chrRaster[intY, intZ + 1] == '*' || chrRaster[intY, intZ] == '*' && chrRaster[intY, intZ + 1] == '.')
{
}
}
Console.WriteLine();
}
int intm = 0;
return intm;
}
}
One way to do this would be to make a copy of the array and then iterate over it, examining each item. If the item is a '.', then update the neighbors of this item in the original array.
To determine the neighbors, we simply add one to the row to get the neighbor below, subtract one from the row to get the neighbor above, and similarly we can get the right and left neighbors by adding/subtracting from the column value. Of course we need to ensure that we're inside the bounds of the array before doing anything.
We could write a method with this logic that might look like:
private static void ExposeDotNeighbors(char[,] input)
{
if (input == null) return;
// Make a copy of the input array that we can iterate over
// so that we don't analyze items that we've already changed
var copy = (char[,]) input.Clone();
for (var row = 0; row <= copy.GetUpperBound(0); row++)
{
for (var col = 0; col <= copy.GetUpperBound(1); col++)
{
if (copy[row, col] == '.')
{
// Update neighbors in original array
// Above = [row - 1, col], Below = [row + 1, col],
// Left = [row, col - 1], Right = [row, col + 1]
// Before updating, make sure we're inside the array bounds
if (row > 0) input[row - 1, col] = '.';
if (row < input.GetUpperBound(0)) input[row + 1, col] = '.';
if (col > 0) input[row, col - 1] = '.';
if (col < input.GetUpperBound(1)) input[row, col + 1] = '.';
}
}
}
}
We can also write some helper methods that will give us the initial array and to print an array to the console (also one that will write a header to the console):
private static char[,] GetInitialArray()
{
var initialArray = new char[4, 5];
for (var row = 0; row <= initialArray.GetUpperBound(0); row++)
{
for (var col = 0; col <= initialArray.GetUpperBound(1); col++)
{
if ((row == 1 && col == 2) || (row == 3 && col == 4))
{
initialArray[row, col] = '.';
}
else
{
initialArray[row, col] = '*';
}
}
}
return initialArray;
}
private static void PrintArrayToConsole(char[,] input)
{
if (input == null) return;
for (var row = 0; row <= input.GetUpperBound(0); row++)
{
for (var col = 0; col <= input.GetUpperBound(1); col++)
{
Console.Write(input[row, col]);
}
Console.WriteLine();
}
}
private static void WriteHeader(string headerText)
{
if (string.IsNullOrEmpty(headerText))
{
Console.Write(new string('═', Console.WindowWidth));
return;
}
Console.WriteLine('╔' + new string('═', headerText.Length + 2) + '╗');
Console.WriteLine($"║ {headerText} ║");
Console.WriteLine('╚' + new string('═', headerText.Length + 2) + '╝');
}
With these helper methods, we can then write code like:
private static void Main()
{
var chrRaster = GetInitialArray();
WriteHeader("Before");
PrintArrayToConsole(chrRaster);
ExposeDotNeighbors(chrRaster);
WriteHeader("After");
PrintArrayToConsole(chrRaster);
GetKeyFromUser("\nDone! Press any key to exit...");
}
And out output would look like:
I noticed that you also appear to be getting the values from the user, and using try/catch blocks to validate the input. A better approach might be to write a helper method that takes in a string that represents the "prompt" to the user, and a validation method that can be used to validate the input. With this, we can keep asking the user for input until they enter something valid.
Below are methods that get an integer and a character from the user, and allow the caller to pass in a function that can be used for validation. These methods will not return until the user enters valid input:
private static char GetCharFromUser(string prompt, Func<char, bool> validator = null)
{
char result;
var cursorTop = Console.CursorTop;
do
{
ClearSpecificLineAndWrite(cursorTop, prompt);
result = Console.ReadKey().KeyChar;
} while (!(validator?.Invoke(result) ?? true));
Console.WriteLine();
return result;
}
private static int GetIntFromUser(string prompt, Func<int, bool> validator = null)
{
int result;
var cursorTop = Console.CursorTop;
do
{
ClearSpecificLineAndWrite(cursorTop, prompt);
} while (!int.TryParse(Console.ReadLine(), out result) ||
!(validator?.Invoke(result) ?? true));
return result;
}
private static void ClearSpecificLineAndWrite(int cursorTop, string message)
{
Console.SetCursorPosition(0, cursorTop);
Console.Write(new string(' ', Console.WindowWidth));
Console.SetCursorPosition(0, cursorTop);
Console.Write(message);
}
We can then re-write our GetInitialArray method to use these methods to get the dimensions and values from the user:
private static char[,] GetInitialArray()
{
const int maxCols = 20;
const int maxRows = 20;
var numCols = GetIntFromUser(
$"How many columns do you want (1 - {maxCols}): ",
i => i > 0 && i <= maxCols);
var numRows = GetIntFromUser(
$"How many rows do you want (1 - {maxRows}): ",
i => i > 0 && i <= maxRows);
var initialArray = new char[numRows, numCols];
for (var row = 0; row <= initialArray.GetUpperBound(0); row++)
{
for (var col = 0; col <= initialArray.GetUpperBound(1); col++)
{
initialArray[row, col] = GetCharFromUser(
$"Enter value for [{row}, {col}] ('.' or '*'): ",
c => c == '.' || c == '*');
}
}
return initialArray;
}
And now our output might look like this:
If you try it, notice that you cannot enter an illegal value. The program just waits for you to read the instructions and enter a valid number or character. :)
Here is the algorithm that does what you want. I have tried to explain my code in the comments. The output will match what you're looking for.
static void Main(string[] args)
{
char STAR = '*';
char DOT = '.';
var input = new char[,]
{
{ STAR,STAR,STAR,STAR,STAR},
{ STAR,STAR,DOT,STAR,STAR},
{ STAR,STAR,STAR,STAR,STAR},
{ STAR,STAR,STAR,STAR,DOT}
};
var output = new char[4, 5];
// Copy each from input to output, checking if it touches a '.'
for (int x = 0; x < 4; x++)
{
for (int y = 0; y < 5; y ++)
{
if (input[x, y] == STAR)
{
var isDot = false;
// Check left
if (x > 0)
isDot = input[x - 1, y] == DOT;
// Check right
if (x < 3)
isDot = isDot || (input[x + 1, y] == DOT);
// Check above
if (y > 0)
isDot = isDot || (input[x, y - 1] == DOT);
// Check below
if (y < 4)
isDot = isDot || (input[x, y + 1]) == DOT;
output[x, y] = isDot ? DOT : STAR;
}
else
{
output[x, y] = input[x, y];
}
}
}
// Print output
for (int x = 0; x < 4; x ++)
{
for (int y = 0; y < 5; y ++)
{
Console.Write(output[x, y]);
}
Console.WriteLine();
}
Console.Read();
}
You can go like this :
using System;
public class chars
{
public static void Main(string[] args)
{
char[,] charArray = new char[,] {{'*','*','*','*','*'},
{'*','*','.','*','*'},
{'*','*','*','*','*'},
{'*','*','*','*','.'}};
int[,] holdIndex = new int[4, 5];
for(int i = 0; i<4; i++) // get allindexes containing '.'
{
for(int j = 0; j<5; j++)
{
if(charArray[i,j] == '.')
holdIndex[i,j] = 1;
else
holdIndex[i,j] = 0;
}
}
for(int i = 0; i<4; i++)
{
for(int j = 0; j<5; j++)
{
if(holdIndex[i,j] == 1)
{
if(i!=0)
charArray[i-1,j] = '.'; //up
if(j!=0)
charArray[i,j-1] = '.'; // left
if(j!=4)
charArray[i,j+1] = '.'; //right
if(i!=3)
charArray[i+1,j] = '.'; //down
}
}
}
for(int i = 0; i<4; i++)
{
for(int j = 0; j<5; j++)
{
Console.Write(charArray[i,j]);
}
Console.WriteLine();
}
Console.Read();
}
}
Here's the part 1 of my question, if you wanna check the background of this question :
Detecting brackets in input string
Forgive me if the title doesn't match, since I also confused how to name it appropriately to picture my problem. If anyone knows a more appropriate title, feel free to edit.
So, given below code (my own code) :
private const int PARTICLE_EACH_CHAR = 4;
/*ProcessBarLines : string s only contains numbers, b, [, and ]*/
private int ProcessBarLines(Canvas canvas, string s, int lastLineAboveNotation)
{
List<int> bracket = new List<int>();
List<int> other = new List<int>();
int currentCloseNumber = 0;
int currentOpenNumber = 0;
for (int i = 0; i < s.Length; i++)
{
if (s[i] == '[')
{
bracket.Add(i);
currentOpenNumber++;
if (i - 1 > 0 && s[i - 1] != '[')
{
currentOpenNumber = 1;
}
}
else if (s[i] == ']')
{
bracket.Add(i);
currentCloseNumber++;
if (i + 1 >= s.Length || s[i + 1] != ']' || currentOpenNumber == currentCloseNumber)
{
int min = bracket.Count - (currentCloseNumber * 2);
int max = bracket[bracket.Count - 1];
List<int> proc = new List<int>();
int firstIndex = -1;
int lastIndex = -1;
for (int ii = 0; ii < other.Count; ii++)
{
if (other[ii] > min && other[ii] < max)
{
proc.Add(other[ii]);
if (firstIndex == -1)
{
firstIndex = ii;
lastIndex = ii;
}
else
{
lastIndex = ii;
}
}
}
double leftPixel = firstIndex * widthEachChar;
double rightPixel = (lastIndex * widthEachChar) + widthEachChar;
DrawLine(canvas, currentCloseNumber, leftPixel,
rightPixel, lastLineAboveNotation * heightEachChar / PARTICLE_EACH_CHAR);
lastLineAboveNotation += currentCloseNumber - 1;
currentOpenNumber -= currentCloseNumber;
currentCloseNumber = 0;
}
}
else
{
other.Add(i);
}
}
return lastLineAboveNotation + 1;
}
Here's the test cases :
Picture 1 & 2 is the correct answer, and picture 3 is the wrong answer. Picture 3 should have a line, just like inverted from number 2, but, apparently, (if you look closely) the line is drawn on the right, but it should be on the left to be correct (above 0).
I figured, the problem is, I'm quite sure on the "min". Since it doesn't give the correct starting value.
Any idea on this? Feel free to clarify anything. It's used for writing numeric musical scores.
Btw, DrawLine() just meant to draw the line above the numbers, it's not the problem.
Finally! I found it!
private int ProcessBarLines(Canvas canvas, string s, int lastLineAboveNotation)
{
List<int> bracket = new List<int>();
List<int> other = new List<int>();
int currentCloseNumber = 0;
int currentOpenNumber = 0;
int space = 0;
for (int i = 0; i < s.Length; i++)
{
if (s[i] == '[')
{
bracket.Add(i);
currentOpenNumber++;
if (i - 1 > 0 && s[i - 1] != '[')
{
currentOpenNumber = 1;
}
}
else if (s[i] == ']')
{
bracket.Add(i);
currentCloseNumber++;
if (i + 1 >= s.Length || s[i + 1] != ']' || currentOpenNumber == currentCloseNumber)
{
int min = bracket[Math.Max(bracket.Count - ((currentCloseNumber * 2) + space), 0)];
int max = bracket[bracket.Count - 1];
space = max - min - 1;
List<int> proc = new List<int>();
int firstIndex = -1;
int lastIndex = -1;
for (int ii = 0; ii < other.Count; ii++)
{
if (other[ii] > min && other[ii] < max)
{
proc.Add(other[ii]);
other[ii] = -1;
if (firstIndex == -1)
{
firstIndex = ii;
lastIndex = ii;
}
else
{
lastIndex = ii;
}
}
}
double leftPixel = firstIndex * widthEachChar;
double rightPixel = (lastIndex * widthEachChar) + widthEachChar;
DrawLine(canvas, currentCloseNumber, leftPixel,
rightPixel, lastLineAboveNotation * heightEachChar / PARTICLE_EACH_CHAR);
lastLineAboveNotation += 1;
currentOpenNumber -= currentCloseNumber;
currentCloseNumber = 0;
}
}
else
{
other.Add(i);
}
}
return lastLineAboveNotation + 1;
}
If someone got a more efficient code, please let us know!
I have a function to check neighbors of an array and if that element is equal with 1. X is for each neighbor found and v[l] is the position for each 0. I have a problem with this code each time gives me "Index was outside the bounds of the array" and i don't know what to do else.
public int modificari(int i,int j,int n,int m)
{
int x = 0;
v = new int[n];
l=0;
if (mat[i, j] == 1)
{
if (j++ < m)
{
if (mat[i, j++] == 1)
x++;
else
{
v[l] = i * n + j + 2;
l++;
}
}
if (j++ < m && i++ < n)
{
if (mat[i++, j++] == 1)
x++;
else
{
v[l] = (i + 1) * n + j + 2;
l++;
}
}
if (i++ < n)
{
if (mat[i++, j] == 1)
x++;
else
{
v[l] = (i + 1) * n + j + 1;
l++;
}
}
if (j-- >= 0 && i++ < n)
{
if (mat[i++, j--] == 1)
x++;
else
{
v[l] = (i + 1) * n + j;
l++;
}
}
if (j-- >= 0)
{
if (mat[i, j--] == 1)
x++;
else
{
v[l] = i * n + j;
l++;
}
}
if (j-- >= 0 && i-- >= 0)
{
if (mat[i--, j--] == 1)
x++;
else
{
v[l] = (i - 1) * n + j;
l++;
}
}
if (i-- >= 0)
{
if (mat[i--, j] == 1)
x++;
else
{
v[l] = (i - 1) * n + j + 1;
l++;
}
}
if (j < n && i-- >= 0)
{
if (mat[i--, j++] == 1)
x++;
else
{
v[l] = (i - 1) * n + j + 2;
l++;
}
}
if (x < 2 && x > 3)
return 1;
else
return random();
}
return x;
}
That is a total mess. It is very hard to follow, even for an experienced coder. Use of one letter variable names and inline ++ operators is usually discouraged for the sake of readability.
I've quickly tried to rewrite your function from my best guess of what you're trying to achieve. I'm hoping you can see a different way to approach the problem that suits you better.
NOTE: I did not test this code at all, it probably has compile errors.
public struct Point
{
public int X;
public int Y;
public Point( int x, int y )
{
X = x;
Y = y;
}
}
public class Whatever
{
// ...
// Here is a list of the positions of all the neighbours whose values are
// zero.
List<Point> zeroPositions = new List<Point>();
// ...
public int Modificari(int pointX, int pointY)
{
// Determine dimensions of array.
int height = mat.GetLength(0);
int width = mat.GetLength(1);
// Find the minimum and maximum positions bounded by array size. (So we
// don't try to look at cell (-1, -1) when considering the neighbours of
// cell (0, 0) for instance.
int left = Math.Max( pointX - 1, 0 );
int right = Math.Min( pointX + 1, width );
int top = Math.Max( pointY - 1, 0 );
int bottom = Math.Min( pointY + 1, height );
// This is the number of neighbours whose value is 1.
int oneCount = 0;
zeroPositions.Clear();
for( int y = top; y <= bottom; y++ )
{
for( int x = left; x <= right; x++ )
{
if( mat[x, y] == 1 )
{
oneCount++;
}
else if( mat[x, y] == 0 )
{
zeroPositions.Add( new Point( x, y ) );
}
}
}
return oneCount;
}
//...
}
Also I'd really advise you to try not to do too many things in a function. Try making a different function for getting positions of ones and for returning the number of zeros.