[Java] 蓝桥杯ADV-83 算法提高寻找三位数

问题描述
将1，2，…，9共9个数分成三组，分别组成三个三位数，且使这三个三位数构成
1：2：3的比例，试求出所有满足条件的三个三位数。
例如：三个三位数192，384，576满足以上条件。
输入格式
无输入文件
输出格式
输出每行有三个数，为满足题设三位数。各行为满足要求的不同解。

package adv83;

import java.util.Scanner;

public class Main {

    private static int[] num;
    
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        num = new int[9];
        in.close();
        dfs(0);
    }

    private static void dfs(int pos) {
        if (pos == 9) {
            int one = num[0] * 100 + num[1] * 10 + num[2];
            int two = num[3] * 100 + num[4] * 10 + num[5];
            int three = num[6] * 100 + num[7] * 10 + num[8];
            
            if (one * 2 == two && one * 3 == three) {
                System.out.println(one + " " + two + " " + three);
            }
            
            return;
        }
        
        for (int i = 1; i <= 9; i++) {
            if (isNotSelect(pos, i)) {
                num[pos] = i;
                dfs(pos + 1);
            }
        }
    }
    
    private static boolean isNotSelect(int pos, int value) {
        for (int i = 0; i < pos; i++) {
            if (num[i] == value) {
                return false;
            }
        }
        return true;
    }

}

package adv83;

import java.util.Scanner;

public class Main {

private static int[] num;

public static void main(String[] args) {

Scanner in = new Scanner(System.in);

num = new int[9];

in.close();

dfs(0);

}

private static void dfs(int pos) {

if (pos == 9) {

int one = num[0] * 100 + num[1] * 10 + num[2];

int two = num[3] * 100 + num[4] * 10 + num[5];

int three = num[6] * 100 + num[7] * 10 + num[8];

if (one * 2 == two && one * 3 == three) {

System.out.println(one + " " + two + " " + three);

}

return;

}

for (int i = 1; i <= 9; i++) {

if (isNotSelect(pos, i)) {

num[pos] = i;

dfs(pos + 1);

}

private static boolean isNotSelect(int pos, int value) {

for (int i = 0; i < pos; i++) {

if (num[i] == value) {

return false;

}

return true;

}

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