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Find K-Sum Subsets

Explore how to identify all subsets of distinct positive integers that add up to a target sum k. This lesson helps you understand the subset sum problem, apply effective logic, and prepare an efficient solution with O(n * 2^n) time complexity. Gain hands-on practice to refine your coding interview skills with subset problems.

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Statement

Given an array of nn distinct positive integers, find all possible subsets of these integers such that the sum of the elements in each subset equals a given target value k.

Return a 2D array, where each inner array represents a subset whose sum equals k.

Constraints:

  • 1≤n≤101 \leq n \leq 10

  • 1≤x≤1001 \leq x \leq 100, where xx is any member of the input array.

  • 1≤1 \leq k ≤103\leq 10^3

Examples

Understand the problem

Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

Find K-Sum Subsets

1.

From the given set, find all subsets with sum equals k:

set = {8, 13, 3, 22, 17, 39, 87, 45, 36}

k = 16

A.

{8, 3}

B.

{13, 3}

C.

{13, 8}

D.

{22, 17}

1 / 3

Figure it out!

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Note: As an additional challenge, we have intentionally hidden the solution to this puzzle.

Sequence - Vertical
Drag and drop the cards to rearrange them in the correct sequence.
1
2
3
4
5
6

Try it yourself

Implement your solution in the following coding playground.

We have left the solution to this challenge as an exercise for you. An optimal solution to this problem runs in O(n * 2n) time and takes O(n) space. You may try to translate the logic of the solved puzzle into a coded solution.

Java
usercode > Solution.java
import java.util.*;



public class Solution{

    public static List<List<Integer>> getKSumSubsets(int[] nums, int k) {

      // Replace this placeholder return statement with your code

      return new ArrayList<>();

    }

}
Find K-Sum Subsets