## In this example, you’ll learn to calculate the sum of natural numbers.

To understand this Program to Calculate Sum of Natural Numbers, you should have the knowledge of following C++ programming topics:

- C++ for Loop

Positive integers 1, 2, 3, 4… are known as natural numbers.

This program takes a positive integer from the user( suppose the user entered `n` ) then, this program displays the value of 1+2+3+….+n.

#### Program to find Sum of Natural Number using loop

#include <iostream> using namespace std; int main() { int n, sum = 0; cout << "Enter a positive integer: "; cin >> n; for (int i = 1; i <= n; ++i) { sum += i; } cout << "Sum = " << sum; return 0; }

**Output**

Enter a positive integer: 50 Sum = 1275

This program assumes that user always enters the positive number.

If the user enters the negative number, **Sum = 0** is displayed and the program is terminated.

This program can also be done using recursion. Check out this article for calculating the sum of natural numbers using recursion.

#### Related Program

- C++ Program to check leap year.
- C++ Program to find factorial.
- C++ Program to generate Multiplication table.
- C++ Program to display Fibonacci series.
- C++ Program to find GCD using for and while loop.
- C++ Program to find LCM.
- C++ Program to reverse integer or number.
- C++ Program to display factors of a Number.

Ask your questions and clarify your/others doubts on Sum of Natural Number by commenting.** Documentation**