import java.util.*;
public class Nqueens{
    static int n;
    static int[][] board;

    static boolean isSafe(int r, int c){
        for(int i=0;i<r;i++){
            if(board[i][c]==1)
                return false;
        }
        for(int i=r,j=c;i>=0 && j>=0;i--,j--){
            if(board[i][j]==1)
                return false;
        }
        for(int i=r,j=c;i>=0 && j<n;i--,j++){
            if(board[i][j]==1)
                return false;
        }
        return true;

    }

    static void solve(int r){
        if(r==n){
            for(int i=0;i<n;i++){
                for(int j=0;j<n;j++){
                    if(board[i][j]==1){
                        System.out.print(" Q ");
                    }else
                        System.out.print(" . ");
                }
                System.out.println();
            }
            System.out.println();
            return;
            
        }
        for(int i=0;i<n;i++){
            if(isSafe(r,i)){
                board[r][i] =1;
                solve(r+1);
                board[r][i]=0;
            }

            
        }
    }
    public static void main(String[] args){
        Scanner sc= new Scanner(System.in);
        System.out.print("\nEnter n: ");
        n =sc.nextInt();
        board = new int[n][n];
        solve(0);
        sc.close();

    }
}