组成最大数 华为机试

【题目描述】

【示例】

【解题思路】

【代码】

package Huawei;

import java.util.LinkedList;
import java.util.Scanner;

/**
 * @description:
 * @author: Polaris
 * @date: 2022/3/30 14:37
 */
public class no8 {
    static int ans=0;
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()){
            String[] str = sc.nextLine().split(",");
            int[] arr = new int[str.length];
            for(int i=0;i<str.length;i++){
                arr[i] = Integer.parseInt(str[i]);
            }
            maxNum(arr,new LinkedList<Integer>(),new boolean[arr.length]);
            System.out.println(ans);
        }
    }
    static void maxNum(int[] arr, LinkedList<Integer> track, boolean[] used){
        if(track.size()==arr.length){
            String sum = "";
            for(int i:track){
                sum+=i;
            }
            ans = Math.max(Integer.parseInt(sum),ans);
        }

        for(int i =0;i<arr.length;i++){
            if(used[i]){
                continue;
            }
            used[i] = true;
            track.add(arr[i]);
            maxNum(arr,track,used);
            track.removeLast();
            used[i] = false;
        }
    }

}