C# Source Code

// eight-queens
// Author: Hannes du Plooy 
// Date: 20 Sep 2016      
// Objective: To solve the following
// Search for a chess board solution with 8 queens and no one
// endangering any other.
using System;
using System.IO;

namespace EightQueensNS {
    public class EightQueensClass {
        static int[] board = new int[8];
        
        static bool EightQueens(int line) {
            if (line > 7) {
                return true;
            }
            for(int column=0;column<8;column++) {
                bool endangered = false;
                for(int line2=0;line2<line;line2++) {
                    if (board[line2] == column || Math.Abs(line-line2) == Math.Abs(column-board[line2])) {
                        endangered = true;
                        break;
                    }
                }
                if (!endangered) {
                    board[line] = column;
                    if (EightQueens(line+1)) {
                        return true;
                    }
                }
            }
            return false;
        }

        static void Main(string[] args) {
            if (EightQueens(0)) {
                for(int i=0;i<8;i++) {
                    for(int j=0;j<8;j++) {
                        if (board[i] == j) {
                            Console.Write("Q");
                        } else {
                            Console.Write(".");
                        }
                    }
                    Console.WriteLine();
                }
            } else {
                Console.WriteLine("No Solution");
            }
        }
    }
}