Java: Sum of all the elements from all possible subsets of a set formed by first n natural numbers

Last update on March 10 2025 12:23:21 (UTC/GMT +8 hours)

Subset Sums of Natural Numbers

Write a Java program that accepts an integer and sums the elements from all possible subsets of a set formed by the first n natural numbers.

Sample Solution:

Java Code:

// Import Scanner class from java.util package for user input
import java.util.Scanner;

// Main class for the solution
public class Solution {

    // Main method to execute the solution
    public static void main(String[] args) {
        // Create a Scanner object for user input
        Scanner in = new Scanner(System.in);

        // Prompt the user to input a positive integer
        System.out.print("Input a positive integer: ");

        // Read the user input as an integer
        int n = in.nextInt();

        // Calculate the sum of subsets using a mathematical formula
        int result = (n * (n + 1) / 2) * (1 << (n - 1));

        // Display the result of the sum of subsets
        System.out.print("Sum of subsets of n is : " + result);
    }
} 

Sample Output:

Input a positive integer:  25
Sum of subsets of n is : 1157627904

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to count the number of subsets of the first n natural numbers that sum to a specified target value.
• Write a Java program to determine the maximum subset sum of the first n natural numbers that does not exceed a given limit.
• Write a Java program to generate and list all possible subset sums from the first n natural numbers.
• Write a Java program to compute the subset sums of the first n natural numbers that are even.

Java Code Editor:

Company:  Bloomberg

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