题目描述

blablabla

样例

blablabla

import java.util.Scanner;

public class Main {
static int n;
static char[][] g;
static boolean[] col;
static boolean[] dg;
static boolean[] udg;

public static void dfs(int u){
    if(u == n){
        for(int i=0;i<n;i++){
            for(int j = 0;j<n;j++){
                System.out.print(g[i][j]);
            }
            System.out.println();
        }
        System.out.println();
        return;
    }
    for(int i=0;i< n;i++){
        if(!col[i] && !dg[i+u] && !udg[i -u+n-1]) {
            g[u][i] = 'Q';
            col[i] = true;
            dg[u+i] = true;
            udg[i-u+n-1] = true;
            dfs(u+1);
            col[i] = false;
            dg[u+i] = false;
            udg[i-u+n-1] = false;
            g[u][i] = '.';

        }
    }
}

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    n = sc.nextInt();
    g = new char[n][n];
    col = new boolean[n];
    dg = new boolean[2*n-1];
    udg = new boolean[2*n-1];
    for(int i = 0;i<n;i++){
        for(int j = 0;j<n;j++){
            g[i][j] = '.';
        }
    }
    dfs(0);
}

}