TextFile1.txt

// N queen - Reset Repair Hill Climbing.cpp
// open-mind.ir
 
#include "stdafx.h"
#include <vector>
#include <iostream>
#include <fstream>
#include <time.h>
#include <iomanip>
 
 
using namespace std;
 
//print solution in console
void printBoardinTerminal(int *board, int len)
{
	for (int i = 0; i < len; i++)
	{
		for (int j = 0; j < len; j++)
		{
			if (j == board[i])
			{
				cout << 1 << " ";
			}
			else
			{
				cout << 0 << " ";
			}
		}
		cout << endl;
	}
}
 
//print solution in File
void printBoardinFile(int *board, int len)
{
	ofstream fp("output.txt", ios::out);
 
	fp << "Answer for " << len << " queen: \n \n";
 
	for (int i = 0; i < len; i++)
	{
		for (int j = 0; j < len; j++)
		{
			fp << "----";
		}
		fp << "\n|";
 
		for (int j = 0; j < len; j++)
		{
			if (j == board[i])
			{
				fp << setw(4) << "* |" ;
			}
			else
			{
				fp << setw(4) << "  |";
			}
		}
		fp << "\n";
	}
}
 
//The number of queens couples who are threatened themself
int evaluate(int *board, int len)
{
	int score = 0;
	for (int i = 0; i < len - 1; i++)
	{
		for (int j = i + 1; j < len; j++)
		{
			if (board[i] == board[j])
			{
				score++;
				continue;
			}
			if (board[i] - board[j] == i - j)
			{
				score++;
				continue;
			}
			if (board[i] - board[j] ==  j - i)
			{
				score++;
				continue;
			}
		}
	}
	return score;
}
 
//generate new state from current state 
int* generateBoard(int *board,int len)
{
	vector <int> choice;
 
	int temp;
	int score;
	int eval = evaluate(board, len);
	int k;
 
	int *boardOut;
	boardOut = new int [len];
	
	
	for (int i = 0; i < len; i++)
	{
			boardOut[i] = board[i];
	}
 
	for (int i = 0; i < len; i++)
	{
		choice.clear();
 
		choice.push_back(boardOut[i]);
		temp = boardOut[i];
		
		for (int j = 0; j < len; j++)
		{
			boardOut[i] = j;
			
			k = evaluate(boardOut, len);
			
			if (k == eval)
			{
				choice.push_back(j);
			}
			
			if (k < eval)
			{
				choice.clear();
				choice.push_back(j);
				eval = k;
			}
		}
		boardOut[i] = choice[rand() % choice.size()];
	}
 
	return boardOut;
}
 
//in this function , genarate new state by pervious function and if it has better value then replaces that by current state
bool findNextState(int *board, int len)
{
	int maineval = evaluate(board, len);
 
	int *tempBoard;
	
	tempBoard = generateBoard(board, len);
 
	if (evaluate(tempBoard, len) < maineval)
	{
		for (int p = 0; p < len; p++)
		{
			board[p] = tempBoard[p];
		}
 
		return	true;
	}
	
	return false;
}
 
// make random initial state , put one queen in each row
void initialRandomBoard(int * board, int len)
{
	bool access;
	int col;
 
	for (int i = 0; i < len; i++)
	{
		board[i] = rand() % len;
	}
}
 
//this function include a loop that call findNextState function , and do that until reach solution
//if findNextState function return NULL then we reset current state
void SolveNQueen(int len)
{
	cout << "The program is under process! wait!" << endl;
	
	int *board;
	board = new int[len];
	
 
	initialRandomBoard(board, len);
 
	while (evaluate(board, len) != 0)
	{
		if (!findNextState(board, len))
		{
			initialRandomBoard(board, len);
		}
	}
	
 
	//
	cout << endl << "Anwser for " << len << " queens: "<< endl << endl;
	printBoardinTerminal(board, len);
	printBoardinFile(board, len);
	//
}
 
 
int main()
{
	int n;
	srand(time(NULL));
	
	cout << "Enter  number \'N\', \'N\' indicate numbers of queens in \"N * N\" chess board: " << endl;
	cin >> n;
 
	if (n < 4)
	{
		cout << "\'n\' must be uper than 3!" << endl;
		exit(1);
	}
 
	SolveNQueen(n);
	
	cout << endl << "As well , you can see result in \"output.txt\"." << endl << endl;
	
	return 0;
}