In this tutorial, you will learn how to write a C++ Program to find the sum of natural numbers using formula, or a loop statement.

## C++ Sum of Natural Numbers

To find the sum of first n natural numbers in C++, we can use the for loop to iterate from `1` to `n` and accumulate the sum, or we can also use the formula `n(n+1)/2` directly.

In this tutorial, we will write C++ Programs to find the sum of natural numbers, with the two methods mentioned above.

## Programs

### 1. Compute sum of natural numbers using For loop

In the following program, we read a number into `n`, and find the sum of natural numbers from 1 to n, using For Loop.

main.cpp

```#include <iostream>
using namespace std;

int main() {
int n;
cout << "Enter a number  : ";
cin >> n;

int sum = 0;
for(int i = 1; i <= n; i++) {
sum += i;
}

cout << "Sum : " << sum << endl;
}```

Output

```Enter a number  : 5
Sum : 15
Program ended with exit code: 0```
```Enter a number  : 1256
Sum : 789396
Program ended with exit code: 0```

### 2. Compute sum of natural numbers using formula

In the following program, we read a number into `n`, and find the sum of natural numbers from 1 to n, using the formula `n(n+1)/2`.

main.cpp

```#include <iostream>
using namespace std;

int main() {
int n;
cout << "Enter a number  : ";
cin >> n;

int sum = n * (n + 1) / 2;
cout << "Sum : " << sum << endl;
}```

Output

```Enter a number  : 5
Sum : 15
Program ended with exit code: 0```
```Enter a number  : 1256
Sum : 789396
Program ended with exit code: 0```

## Conclusion

In this C++ Tutorial, we learned how to find the sum of first n Natural Numbers.