Sum of Series

Compute the sum of the series 1 + 2 + ... + n using a loop.

JavaBeginner

Java

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter n: ");
        int n = sc.nextInt();

        int sum = 0;
        for (int i = 1; i <= n; i++) {
            sum += i;
        }
        System.out.println("Sum = " + sum);
        sc.close();
    }
}

Output

Enter n: 5
Sum = 15

We accumulate sum in a loop; this is the iterative version of the formula-based sum.

Power of Number

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