We Keep Coding

MiniMax algorithm for 4 in a row

I'm trying to implement minimax algorithm, but it isn't working, the computer is just making moves randomly. Here is the method Minimax and ComputerLogic.
static int MiniMax(int[,] board, int depth, bool isMax)
{
int len = 0;
for (int i = 0; i < board.GetLength(0); i++)
{
for (int j = 0; j < board.GetLength(1); j++)
{
if (board[i, j] == 0) len++;
}
}
int best_score, score;
if (WinVariants(board, 1))
{
best_score = -10;
return best_score;
}
else if (WinVariants(board, 2))
{
best_score = 10;
return best_score;
}
else if (len == 0)
{
best_score = 0;
return best_score;
}
if (isMax)
{
best_score = -int.MaxValue;
for (int i = 0; i < board.GetLength(0); i++)
{
for (int j = 0; j < board.GetLength(1); j++)
{
if (board[i, j] == 0)
{
board[i, j] = 1;
score = MiniMax(board, depth + 1, false);
board[i, j] = 0;
best_score = Math.Max(best_score, score);
}
}
}
}
else
{
best_score = int.MaxValue;
for (int i = 0; i < board.GetLength(0); i++)
{
for (int j = 0; j < board.GetLength(1); j++)
{
if (board[i, j] == 0)
{
board[i, j] = 2;
score = MiniMax(board, depth + 1, true);
board[i, j] = 0;
best_score = Math.Min(best_score, score);
}
}
}
}
return best_score;
}
static void ComputerLogic(int[,] grid, int VariantMove)
{
int[,] board = Copy(grid);
int bestScore = -int.MaxValue, score;
int len = 0;
Random rnd = new Random();
if (len <= 2)
{
while (true)
{
int x = rnd.Next(0, 7);
int y = rnd.Next(0, 7);
len++;
if (grid[x, y] == 0)
{
grid[x, y] = 1;
break;
}
}
}
else
{
while (true)
{
for (int i = 0; i < board.GetLength(0); i++)
{
for (int j = 0; j < board.GetLength(1); j++)
{
if (board[i, j] == 0)
{
board[i, j] = 1;
score = MiniMax(board, 0, false);
board[i, j] = 0;
if (score > bestScore)
{
bestScore = score;
grid[i, j] = 1;
break;
}
}
}
}
}
}
}
Too, i have method for Drawing my grid view 2d array.
If I choose the PC to go first, then it goes randomly. Otherwise, my mesh just isn't drawing.
I am guessing that I am not filling my main grid array correctly. Its copy is used for verification - board.
Can please help me with this problem?

Bubble sort 2D string array

How can I bubble sort a 2D string array by their lenght? In the array's zeroth column there are random generated messages and in the first column there are random generated priorities.
string[,] array = new string[50, 2];
Random r = new Random();
int number = 0;
int space = 0;
double fontossag = 0;
for (int i = 0; i < 50; i++)
{
string message = "";
int hossz = r.Next(10,51);
for (int h = 0; h < hossz; h++)
{
number = r.Next(0,101);
space = r.Next(0, 101);
if (number<=50)
{
message += (char)r.Next(97,122);
}
else if(number >= 50)
{
message += (char)r.Next(65, 90);
}
if (space<=10)
{
message += " ";
}
}
for (int f = 0; f < 50; f++)
{
fontossag = r.NextDouble() * (10.0);
}
array[i, 0] += message;
array[i, 1] += fontossag;
}
I want to sort the array by the random generated messages length.

This is my method to Bubble sort on the first column length:
public static string[,] BubbleSortStringByLength(string[,] array)
{
int num = array.GetLength(0);
for (int i = 0; i < num - 1; i++)
{
for (int j = 0; j < num - i - 1; j++)
{
if (array[j, 0].Length > array[j + 1, 0].Length)
{
// swap first column
string tmp = array[j, 0];
array[j, 0] = array[j + 1, 0];
array[j + 1, 0] = tmp;
// swap second column
tmp = array[j, 1];
array[j, 1] = array[j + 1, 1];
array[j + 1, 1] = tmp;
}
}
}
return array;
}
You can download the Visual Studio solution on GitHub

So you want to compare lengths of 1st columns and swap rows to ensure descending priority:
for (bool hasWork = true; hasWork;) {
hasWork = false;
for (int row = 0; row < array.GetLength(0) - 1; ++row) {
int priority1 = array[row, 0]?.Length ?? -1;
int priority2 = array[row + 1, 0]?.Length ?? -1;
// if we have wrong order...
if (priority1 < priority2) {
// we should keep on working to sort the array
hasWork = true;
// and swap incorrect rows
for (int column = 0; column < array.GetLength(1); ++column)
(array[row, column], array[row + 1, column]) =
(array[row + 1, column], array[row, column]);
}
}
}
Please, fiddle yourself

Creating an isosceles triangle in C3

The code below only makes a right angle triangle, how would I make it into an isosceles triangle?
int height = 4;
string star = "";
for (int i = 0; int i < height; i++)
{
star += "*";
Console.WriteLine(star);
}
Console.ReadLine();
This only displays a right angle triangle. What I attempted to make was a pyramid.

Here you have a cleaner code:
int numberoflayer = 4;
int empty;
int number;
for (int i = 1; i <= numberoflayer; i++)
{
for (empty = 1; empty <= (numberoflayer - i); empty++)
Console.Write(" ");
for (number = 1; number <= i; number++)
Console.Write('*');
for (number = (i - 1); number >= 1; number--)
Console.Write('*');
Console.WriteLine();
}

This draws your christmas tree:
int height = 4;
for (int i = 0; i < height; i++)
{
int countSpaces = (int)Math.Ceiling((height * 2 / 2d) - i);
int countStars = 1 + (i * 2);
string line = new string(' ', countSpaces) + new string('*', countStars);
Console.WriteLine(line);
}

Dirty code but there you go
int height = 4;
string empty = " ";
String star = "";
for(int i = 0; i<height; i++)
{
star += " *";
empty = empty.Length > 0 ? empty.Remove(0,1) : " ";
Console.WriteLine(empty + star);
}
Console.ReadLine();

Rotating matrices

Objectives
Imagine that, we have matrix like
a11 a12 a13
a21 a22 a23
a31 a32 a33
What I want to do is, from textbox value rotate this matrix so that, for example if I write 2 and press rotate, program must keep both diagonal values of matrix (in this case a11, a22, a33, a13, a31) and rotate 2 times clockwise other values. So result must be like
a11 a32 a13
a23 a22 a21
a31 a12 a33
It must work for all N x N size matrices, and as you see every 4 rotation takes matrix into default state.
What I've done
So idea is like that, I have 2 forms. First takes size of matrix (1 value, for example if it's 5, it generates 5x5 matrix). When I press OK it generates second forms textbox matrix like that
Form 1 code
private void button1_Click(object sender, EventArgs e)
{
int matrixSize;
matrixSize = int.Parse(textBox1.Text);
Form2 form2 = new Form2(matrixSize);
form2.Width = matrixSize * 50 + 100;
form2.Height = matrixSize *60 + 200;
form2.Show();
//this.Hide();
}
Form 2 code generates textbox matrix from given value and puts random values into this fields
public Form2(int matrSize)
{
int counter = 0;
InitializeComponent();
TextBox[] MatrixNodes = new TextBox[matrSize*matrSize];
Random r = new Random();
for (int i = 1; i <= matrSize; i++)
{
for (int j = 1; j <= matrSize; j++)
{
var tb = new TextBox();
int num = r.Next(1, 1000);
MatrixNodes[counter] = tb;
tb.Name = string.Format("Node_{0}{1}", i, j);
Debug.Write(string.Format("Node_{0}{1}", i, j));
tb.Text = num.ToString();
tb.Location = new Point(j * 50, i * 50);
tb.Width = 30;
tb.Visible = true;
this.splitContainer1.Panel2.Controls.Add(tb);
counter++;
}
}
}
Form 2 has 1 textbox for controlling rotation (others are generated on the fly, programmatically). What I want to do is, when I enter rotation count and press Enter on this textbox, I want to rotate textbox matrix as I explained above. Can't figure out how to do it.

Copy both diagonals to separate arrays, then rotate your matrix and replace diagonals. Below code shows each step:
class Program
{
static void Main(string[] args)
{
int matrixSize = 3;
string[,] matrix = new string[matrixSize,matrixSize];
//create square matrix
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
matrix[x, y] = "a" + (x + 1).ToString() + (y + 1).ToString();
}
}
Console.WriteLine(Environment.NewLine + "Base square matrix");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(matrix[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//copy diagonals
string[] leftDiagonal = new string[matrixSize];
string[] rightDiagonal = new string[matrixSize];
for (int x = 0; x < matrixSize; x++)
{
leftDiagonal[x] = matrix[x, x];
rightDiagonal[x] = matrix[matrixSize - 1 - x, x];
}
Console.WriteLine(Environment.NewLine + "Diagonals");
for (int x = 0; x < matrixSize; ++x)
{
Console.Write(leftDiagonal[x] + " " + rightDiagonal[x] + Environment.NewLine);
}
Console.ReadKey();
//rotate matrix
string[,] rotatedMatrix = new string[matrixSize, matrixSize];
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
rotatedMatrix[x, y] = matrix[matrixSize - y - 1, x];
}
}
Console.WriteLine(Environment.NewLine + "Rotated");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrix[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//rotate matrix again
string[,] rotatedMatrixAgain = new string[matrixSize, matrixSize];
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
rotatedMatrixAgain[x, y] = rotatedMatrix[matrixSize - y - 1, x];
}
}
Console.WriteLine(Environment.NewLine + "Rotated again");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrixAgain[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//replace diagonals
for (int x = 0; x < matrixSize; x++)
{
rotatedMatrixAgain[x, x] = leftDiagonal[x];
rotatedMatrixAgain[matrixSize - 1 - x, x] = rightDiagonal[x];
}
Console.WriteLine(Environment.NewLine + "Completed" + Environment.NewLine);
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrixAgain[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
}
}

I don't know C#, so I can only give a suggestion in pseudocode:
Input: An N by N matrix in
Output: The input matrix rotated as described in the OP out
for i = 1 to N
for j = 1 to N
if N - j != i and i != j // Do not change values on either diagonal
out[j][N-i] = in[i][j]
else
out[i][j] = in[i][j]
Disclaimer: This algorithm is untested. I suggest you use a debugger to check that it works as you want.

This seems like quite an unorthodox UI presentation, but you're not too far off in terms of being able to achieve your functionality. Instead of a linear array, a rectangular array will make your job much easier. The actual rotation could be implemented with a for loop repeating a single rotation (which would be implemented as in the case 1 code), but I've decided to combine them into the four possible cases. This actually allows you to enter a negative number for number of rotations. Which reminds me, you really should do more error checking. At least protect against int.Parse throwing an exception both places it's used (with a try catch block or by switching to int.TryParse) and make sure it returns a meaningful number (greater than 0, possibly set a reasonable maximum other than int.MaxValue) for matrixSize in button1_Click.
namespace RotatingMatrices
{
public class Form2 : Form
{
// note these class fields
private TextBox[,] matrixNodes;
private int matrixSize;
public Form2(int matrSize)
{
InitializeComponent();
// note these inits
matrixSize = matrSize;
matrixNodes = new TextBox[matrixSize, matrixSize];
Random r = new Random();
// note the new loop limits
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
var tb = new TextBox();
int num = r.Next(1, 1000);
// note the change in indexing
matrixNodes[i,j] = tb;
tb.Name = string.Format("Node_{0}_{1}", i, j);
Debug.Write(string.Format("Node_{0}_{1}", i, j));
tb.Text = num.ToString();
tb.Location = new Point(j * 50, i * 50);
tb.Width = 30;
tb.Visible = true;
this.splitContainer1.Panel2.Controls.Add(tb);
}
}
}
private void buttonRotate_Click(object sender, EventArgs e)
{
string[,] matrix = new string[matrixSize, matrixSize];
int rotations = (4 + int.Parse(textBoxRotations.Text)) % 4; // note the addition of and mod by 4
switch(rotations)
{
case 1: // rotate clockwise
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[j, matrixSize - i - 1] = matrixNodes[i, j].Text;
}
}
break;
case 2: // rotate 180 degrees
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[i, j] = matrixNodes[matrixSize - i - 1, matrixSize - j - 1].Text;
}
}
break;
case 3: // rotate counter-clockwise
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[i, j] = matrixNodes[j, matrixSize - i - 1].Text;
}
}
break;
default: // do nothing
return;
}
// restore diagonals
for(int i = 0; i < matrixSize; i++)
{
matrix[i, i] = matrixNodes[i, i].Text;
matrix[i, matrixSize - i - 1] = matrixNodes[i, matrixSize - i - 1].Text;
}
// write strings back to text boxes
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrixNodes[i, j].Text = matrix[i, j];
}
}
}
}
}

I decided to tackle the issue using a listView instead of a text box, which makes the logic easier for me. Using this method, I was able to think of the matrix as successive boxes. I start on the outside and move in toward the middle, changing the size of my box each time.
Also, rather than using two forms, I use one. At the top I have a textbox where the user enters the size they want the array to be, and a button labeled "Fill" (button2). And at the bottom I have a textbox where the user enters the degree of rotation. When they click "Rotate," it kicks off a process of adding values to linked lists, combining and shifting the list, and then writing back out to the matrix. I'm sure I made it more convoluted than it has to be, but it was a great learning exercise.
After looking over jerry's code above, I think I'm going to look into rectangular arrays. :)
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Recycle
{
public partial class Form1 : Form
{
public int size;
public LinkedList<string> topRight = new LinkedList<string>();
public LinkedList<string> bottomLeft = new LinkedList<string>();
public LinkedList<string> myMatrix = new LinkedList<string>();
public LinkedList<string> shiftMatrix = new LinkedList<string>();
public Form1()
{
InitializeComponent();
}
private void button2_Click(object sender, EventArgs e)
{
listView1.Clear();
size = int.Parse(textBox2.Text);
int c = 0;
int q = 0;
int w = 0;
string[] content = new string[size];
Random rnd = new Random();
for (c = 0; c < size; c++)
{
listView1.Columns.Add("", 25);
}
for (q = 0; q < size; q++)
{
for (w = 0; w < size; w++)
{
content[w] = rnd.Next(9,100).ToString();
}
ListViewItem lvi = new ListViewItem(content);
listView1.Items.Add(lvi);
}
}
public bool iseven(int size)
{
if (size % 2 == 0)
{
return true;
}
else
{
return false;
}
}
public void button1_Click(object sender, EventArgs e)
{
if (listView1.Items.Count < 3)
{
MessageBox.Show("Matrix cannot be rotated.");
return;
}
bool even = false;
int shift = int.Parse(textBox1.Text); //amount to shift by
int box = listView1.Items.Count - 1; //size of box
int half = Convert.ToInt32(listView1.Items.Count / 2);
int corner = 0; //inside corner of box
if (shift > listView1.Items.Count)
{
shift = shift % ((listView1.Items.Count - 2) * 4);
}
do
{
eachPass(shift, box, corner);
++corner;
--box;
} while (box >= half + 1);
}
public void eachPass(int shift, int box, int corner)
{
int x;
int i;
//Read each non-diagonal value into one of two lists
for (x = corner + 1; x < box; x++)
{
topRight.AddLast(listView1.Items[corner].SubItems[x].Text);
}
x = box;
for (i = corner + 1; i < box; i++)
{
topRight.AddLast(listView1.Items[i].SubItems[x].Text);
}
for (x = box - 1; x > corner; x--)
{
bottomLeft.AddLast(listView1.Items[box].SubItems[x].Text);
}
x = corner;
for (i = box - 1; i > corner; i--)
{
bottomLeft.AddLast(listView1.Items[i].SubItems[x].Text);
}
string myTest = "";
//join the two lists, so they can be shifted
foreach (string tR in topRight)
{
myMatrix.AddLast(tR);
}
foreach (string bL in bottomLeft)
{
myMatrix.AddLast(bL);
}
int sh;
//shift the list using another list
for (sh = shift; sh < myMatrix.Count; sh++)
{
shiftMatrix.AddLast(myMatrix.ElementAt(sh));
}
for (sh = 0; sh < shift; sh++)
{
shiftMatrix.AddLast(myMatrix.ElementAt(sh));
}
//we need the sizes of the current lists
int trCnt = topRight.Count;
int blCnt = bottomLeft.Count;
//clear them for reuse
topRight.Clear();
bottomLeft.Clear();
int s;
//put the shifted values back
for (s = 0; s < trCnt; s++)
{
topRight.AddLast(shiftMatrix.ElementAt(s));
}
for (s = blCnt; s < shiftMatrix.Count; s++)
{
bottomLeft.AddLast(shiftMatrix.ElementAt(s));
}
int tRn = 0;
int bLn = 0;
//write each non-diagonal value from one of two lists
for (x = corner + 1; x < box; x++)
{
listView1.Items[corner].SubItems[x].Text = topRight.ElementAt(tRn);
++tRn;
}
x = box;
for (i = corner + 1; i < box; i++)
{
listView1.Items[i].SubItems[x].Text = topRight.ElementAt(tRn);
++tRn;
}
for (x = box - 1; x > corner; x--)
{
listView1.Items[box].SubItems[x].Text = bottomLeft.ElementAt(bLn);
++bLn;
}
x = corner;
for (i = box - 1; i > corner; i--)
{
listView1.Items[i].SubItems[x].Text = bottomLeft.ElementAt(bLn);
++bLn;
}
myMatrix.Clear();
shiftMatrix.Clear();
topRight.Clear();
bottomLeft.Clear();
}
}
}

Writing stars with specific shape

i want to write a shape with " * " and " | " the shape is below.
The program must take height and width from user.Width is column number without ' | '.I tried to write but confused.My code sometimes works great and sometimes being stupid.For example when i enter height : 13, width : 4 it writes one more,if witdh is 1 it enters infinite loop.While trying to solve it became too conflicted.Must i fix it or rewrite ? Here is the code : height =10, width = 5
|*____|
|_*___|
|__*__|
|___*_|
|____*|
|___*_|
|__*__|
|_*___|
|*____|
|_*___|
private static void Function()
{
int height, width;
if (width == 2)
while (height > 0)
{
FirstPart(width, height);
height -= width;
}
else
while (height > 0)
{
if (height > 1)
{
FirstPart(width, height);
height -= width;
}
if (height > 0)
{
SecondPart(width, height);
height -= width - 2;
}
}
}
private static void FirstPart(int width,int height)
{
if(height > width)
for (int i = 0; i < width; i++)
{
for (int j = 0; j < width+2; j++)
{
if (j == 0 || j == width + 1)
Console.Write("|");
else
if (i + 1 == j)
Console.Write("*");
else
Console.Write(" ");
}
Console.WriteLine();
}
else
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width + 2; j++)
{
if (j == 0 || j == width + 1)
Console.Write("|");
else
if (i + 1 == j)
Console.Write("*");
else
Console.Write(" ");
}
Console.WriteLine();
}
}
private static void SecondPart(int width,int height)
{
if(height > width)
for (int i = 0; i < width-2; i++)
{
for (int j = 0; j < width+2; j++)
{
if (j == 0 || j == width + 1)
Console.Write("|");
else
if (i + j == width-1)
Console.Write("*");
else
Console.Write(" ");
}
Console.WriteLine();
}
else
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width + 2; j++)
{
if (j == 0 || j == width + 1)
Console.Write("|");
else
if (i + j == width - 1)
Console.Write("*");
else
Console.Write(" ");
}
Console.WriteLine();
}
}

private static void WriteStars(int width, int height)
{
int j = 0;
for (int i = 0; i < height; i++)
{
Console.Write("|");
for (int f = 0; f < width; f++)
{
if (f == Math.Abs(j))
{
Console.Write("*");
}
else
{
Console.Write(" ");
}
}
j++;
if (Math.Abs(j) == width - 1)
{
j *= -1;
}
Console.WriteLine("|");
}
}
Probably going to get downvoted for giving you a complete answer, but maybe it'll show you one correct approach and you can learn something from it...

I see a
while (Height > 0)
so your infinite loop is coming from Height never getting less or equal to 0.

It's better to rewrite. When you do, decouple the code into several functions so that one function draws a single line, and another one calls the former to draw all the lines.

void WriteStars(int Width,int Height)
{
int _sp=1; //Star Pos
bool _left = false;
for(int i =0;i<Height;i++)
{
Console.Write("|");
int j;
for(j=1;j<Width-1;j++)
{
if(j==_sp)
{
Console.Write("*");
if(_left)
{
_sp--;
}
else
{
_sp++;
}
j++;
break;
}
else
{
Console.Write("_");
}
}
for(;j<Width-1;j++)
{
Console.Write("_");
}
Console.WriteLine("|");
if(_sp==0)
{
_left = false;
}
else if(_sp==Width)
{
_left = true;
}
}
}
Try if it works, wrote it right here.

even shorter:
static void Variante_2(int height, int width)
{
byte[][] arr = new byte[height][];
int pos = 0;
int mov = 1;
for (int line = 0; line < height; line++)
{
arr[line] = new byte[width];
for (int col = 0; col < width; col++) { arr[line][col] = 45; }
arr[line][pos] = 42;
pos += mov;
if (pos == 0 || pos == (width - 1)) { mov *= -1; }
Console.WriteLine("|" + ASCIIEncoding.ASCII.GetString(arr[line]) + "|");
}
string temp = Console.ReadLine();
}

and it is possible to do it with less code:
static void Variante_3(int height, int width)
{
int pos = 1;
int mov = 1;
for (int line = 0; line < height; line++)
{
Console.WriteLine("|" + "*".PadLeft(pos, '_') + "|".PadLeft(width - pos, '_'));
pos += mov;
if (pos == 1 || pos == (width - 1)) { mov *= -1; }
}
string temp = Console.ReadLine();
}
Sorry to all not doing others homework, but I couldn´t sleep without showing this g