nqueen.cpp

#include<iostream>
#include<math.h>
using namespace std;

int board[20],count;

void print(int n)
{
	int i,j;
	cout<<"\nSolution "<<++count<<":\n";
 	for(i=1;i<=n;++i)
 	{
  		cout<<i;
  		for(j=1;j<=n;++j)
  		{
   			if(board[i]==j)
    		cout<<"\tQ";
   			else
    		cout<<"\t-";
  		}
  		cout<<"\n";
 	}
}

int place(int row,int column)
{
 	int i;
 	for(i=1;i<=row-1;i++)
 	{
  		if(board[i]==column)
   		return 0;
   		if(abs(board[i]-column)==abs(i-row))
    	return 0;
 	}
 	return 1;
}
 
void queen(int row,int n)
{
 	int column;
 	for(column=1;column<=n;column++)
 	{
  		if(place(row,column))
  		{
   			board[row]=column;
   			if(row==n)
    		print(n);
   			else 
    		queen(row+1,n);
		}
	}
}

int main()
{
	int n;
	cout<<"Enter number of Queens:";
	cin>>n;
	queen(1,n);
	return 0;
}