/*Write a Java program to input a number n and calculate the sum of the first n natural numbers:

Sum=1+2+3+...+n

*/

import java.util.Scanner;

public class SumOfNaturalNumbers {

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

// Input

System.out.print("Enter a number: ");

int n = sc.nextInt();

int sum = 0;

// Using for loop

for (int i = 1; i <= n; i++) {

sum += i; // sum = sum + i

}

// Output

System.out.println("Sum of first " + n + " natural numbers = " + sum);

sc.close();

}

}

/* Example Run:

Enter a number: 5

Sum of first 5 natural numbers = 15

*/