题目描述

blablabla

样例

blablabla

java 代码

import java.util.*;

class Main {
    static int n=0;
    static int arr[]=null;
    static boolean flag[]=new boolean[100];
    void dfs(int col){
        if(!check(col)){
            return;
        }
        if (col>=n) {
            for (int i = 0; i <n; i++) {
                for (int j = 0; j <n; j++) {
                    if (j==arr[i])
                        System.out.print("Q");
                    else
                        System.out.print(".");
                }
                System.out.println();
            }
            System.out.println();
            return;
        }
        for (int i = 0; i < n; i++) {
            if (flag[i]) {
                flag[i]=false;
                arr[col] = i;
                dfs(col + 1);
             //   arr[col] = 0;
                flag[i]=true;
            }
        }

    }

    private boolean check(int n) {
        for (int i = 0; i <n-1 ; i++) {
            for (int j = i+1; j <n ; j++) {
                if (Math.abs(arr[i]-arr[j])==Math.abs(i-j))
                    return false;
            }
        }
        return true;
    }

    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        n=scanner.nextInt();
        arr=new int[n];
        Arrays.fill(flag,true);
        new Main().dfs(0);
    }
}