Java 如何求和指数'；a<；性格>；ArrayList

我有一个程序，我已经工作了一段时间了。我需要做一个程序，通过回溯解决用户指定的求和难题。 用户输入三个单独的

字符串

，前两个

字符串

加在一起应等于第三个

字符串

例如：

java + next = scala

4656 + 7980 = 12636

我相信我的思路是正确的，但我需要在

ArrayList

上获取每个值的索引，并使它们的总和小于

20000

。我该怎么做呢

以下是我目前掌握的代码：

import java.util.*;

public class SummationPuzzle 
{

    public static ArrayList<Character> fsList = new ArrayList<Character>();
    public static ArrayList<Character> lastW = new ArrayList<Character>();
    public static ArrayList<Character> finaList = new ArrayList<Character>();

    /**
     * Reads in 3 words entered by user and converts the first two string into a single <Character> ArrayList
     * takes the third string entered and converts it into it's own <Character>ArrayList
     * @param firstW
     * @param secondW
     * @param thirdW
     */
    public static void convertStr(String firstW, String secondW, String thirdW)
    {
        String combined = firstW + secondW; 
        for(int i = 0; i< combined.length(); i++)
        {
            fsList.add(combined.charAt(i));
        }
        for(int j = 0; j< thirdW.length(); j++)
        {
            lastW.add(thirdW.charAt(j));
        }

        System.out.println( fsList +" "+lastW);
        swapAdd(fsList, lastW);
        //feeds the resulting lists into the swapAdd method
    }

    /**@param
     * This method Swaps the first char of fsList with the char at fsList[1]to make sure it matches the char at lastW[1]
     * @param fsList
     * @param lastW
     */
    public static void swapAdd(ArrayList<Character> fsList, ArrayList<Character> lastW)
    {
        Collections.swap(lastW, 0,1);
        System.out.println(lastW + " lastW swap first char");
        char temp = lastW.get(1);
        int j= 0;
        System.out.println(fsList+ " before swap");
        if(!fsList.get(1).equals(temp) && fsList.contains(temp))
        {
            j = fsList.indexOf(temp);
            Collections.swap(fsList,1,j);
        }
        System.out.println(fsList+ " after swap");
        removeDuplicate(fsList, lastW);
    }

    /**
     * Combines two <Character> ArrayList into a one <Character> ArrayList with single instances of the char
     * @param fsList
     * @param lastW
     */
    public static void removeDuplicate(ArrayList<Character> fsList, ArrayList<Character> lastW)
    {
        ArrayList<Character> tempList = new ArrayList<Character>();
        tempList.addAll(fsList);
        tempList.addAll(lastW);
        for(char dupLetter : tempList)
        {
            if(!finaList.contains(dupLetter))
            {
                finaList.add(dupLetter);
            }
        }
        System.out.println(finaList + "This is the list with duplicates removed");
        System.out.println(lastW);

    }


    //main method
    public static void main(String[] args)
    {
        //Receive user input
        Scanner userIn = new Scanner(System.in);
        System.out.println("Please enter your first word");
        String firstW = userIn.next().trim();
        System.out.println("Please enter your Second word");
        String secondW = userIn.next().trim();
        System.out.println("Please enter your Third word");
        String thirdW = userIn.next().trim();


        //print the summation puzzle
        System.out.println(firstW+ " + " + secondW + " = "+ thirdW);
        convertStr(firstW, secondW, thirdW);
    }
}

import java.util.*；
公开课总结难题
{
public static ArrayList fsList=new ArrayList（）；
公共静态ArrayList lastW=新ArrayList（）；
public static ArrayList finaList=new ArrayList（）；
/**
*读入用户输入的3个单词，并将前两个字符串转换为单个ArrayList
*获取输入的第三个字符串并将其转换为自己的ArrayList
*@param firstW
*@param secondW
*@param thirdW
*/
公共静态void convertStr（字符串firstW、字符串secondW、字符串thirdW）
{
组合字符串=firstW+secondW；
对于（int i=0；i

您如何将“java”映射为“4656”等等？在什么逻辑中？那是我的问题映射不是一个选项。所以我必须给每个字符分配一个无映射的数值。我不知道该怎么做。