Challenge Problem!

[mm123]

A Challenge Coding problem!
I got this java code for combinational sum:
*****************************

// Java program to find all combinations that
// sum to a given value
import java.io.*;
import java.util.*;

class GFG {

    static ArrayList<ArrayList<Integer> >
    combinationSum(ArrayList<Integer> arr, int sum)
    {
        ArrayList<ArrayList<Integer> > ans
            = new ArrayList<>();
        ArrayList<Integer> temp = new ArrayList<>();

        // first do hashing since hashset does not always
        // sort
        // removing the duplicates using HashSet and
        // Sorting the arrayList

        Set<Integer> set = new HashSet<>(arr);
        arr.clear();
        arr.addAll(set);
        Collections.sort(arr);

        findNumbers(ans, arr, sum, 0, temp);
        return ans;
    }

    static void
    findNumbers(ArrayList<ArrayList<Integer> > ans,
                ArrayList<Integer> arr, int sum, int index,
                ArrayList<Integer> temp)
    {

        if (sum == 0) {

            // Adding deep copy of list to ans

            ans.add(new ArrayList<>(temp));
            return;
        }

        for (int i = index; i < arr.size(); i++) {

            // checking that sum does not become negative

            if ((sum - arr.get(i)) >= 0) {

                // adding element which can contribute to
                // sum

                temp.add(arr.get(i));

                findNumbers(ans, arr, sum - arr.get(i), i,
                            temp);

                // removing element from list (backtracking)
                temp.remove(arr.get(i));
            }
        }
    }

    // Driver Code

    public static void main(String[] args)
    {
        ArrayList<Integer> arr = new ArrayList<>();

        arr.add(2);
        arr.add(4);
        arr.add(6);
        arr.add(8);

        int sum = 8;

        ArrayList<ArrayList<Integer> > ans
            = combinationSum(arr, sum);

        // If result is empty, then
        if (ans.size() == 0) {
            System.out.println("Empty");
            return;
        }

        // print all combinations stored in ans

        for (int i = 0; i < ans.size(); i++) {

            System.out.print("(");
            for (int j = 0; j < ans.get(i).size(); j++) {
                System.out.print(ans.get(i).get(j) + " ");
            }
            System.out.print(") ");
        }
    }
}

**************************************
what if I have large numbers like 900, 800, 700, 600, 500, 90, 80, 70, 60, 50, 9, 8, 7, 6, 5, 4, 3, 2, 1. and I want the combination of numbers to sum to 2000, how man listed combination. There would be many ones to list, how to limit the pick of 1s or 2s elements if it is going to be too many to list?

 

[Joe4]

Welcome to the Board!

You may have better luck on a Java Script Help Forum, maybe like the one over at "Stack Overflow" (see the second listing here: Top 10 JavaScript Forums, Discussions and Message Boards You Must Follow in 2021).