Merge pull request #3 from SKYICE01/main

added a backtracking formula

chess.cs

@@ -0,0 +1,67 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+namespace Backtracking
+{
+    class chesssolver
+    {
+        static int N;
+        static void printBoard(int[,] board)
+        {
+            for (int i = 0; i < N; i++)
+            {
+                for (int j = 0; j < N; j++)
+                {
+                    Console.Write(board[i, j] + " ");
+                }
+                Console.Write("\n");
+            }
+        }
+        static Boolean toPlaceOrNotToPlace(int[,] board, int row, int col)
+        {
+            int i, j;
+            for (i = 0; i < col; i++)
+            {
+                if (board[row, i] == 1) return false;
+            }
+            for (i = row, j = col; i >= 0 && j >= 0; i--, j--)
+            {
+                if (board[i, j] == 1) return false;
+            }
+            for (i = row, j = col; j >= 0 && i < N; i++, j--)
+            {
+                if (board[i, j] == 1) return false;
+            }
+            return true;
+        }
+        static Boolean theBoardSolver(int[,] board, int col)
+        {
+            if (col >= N) return true;
+            for (int i = 0; i < N; i++)
+            {
+                if (toPlaceOrNotToPlace(board, i, col))
+                {
+                    board[i, col] = 1;
+                    if (theBoardSolver(board, col + 1)) return true;
+
+                    board[i, col] = 0;
+                }
+            }
+            return false;
+        }
+        static void Main(string[] args)
+        {
+            Console.WriteLine("state size of chess table exp '4' if you wish to make blocks out do exp 4[1][2]");
+            N = Convert.ToInt32(Console.ReadLine());
+            int[,] board = new int[N, N];
+            if (!theBoardSolver(board, 0))
+            {
+                Console.WriteLine("Solution not found.");
+            }
+            printBoard(board);
+            Console.ReadLine();
+        }
+    }
+}