# Swift Program – Find Sum of First N Natural Numbers

## Find Sum of First N Natural Numbers

To find sum of first n Natural Numbers, we can use for loop with range `1...n` and accumulate the sum during each iteration. Or, we can use the formula to find the sum of first n Natural Numbers.

## Using For Loop

In the following program, we will take a value of 10 for n, and find the sum of first n Natural Numbers using for loop.

main.swift

``````import Foundation

var n = 10
var sum = 0

for i in 1...n {
sum += i
}

print("The sum of first \(n) natural numbers is \(sum)")``````

Program Output

``The sum of first 10 natural numbers is 55``

## Using Formula

The formula to find the sum of first n Natural Number is n(n+1)/2. In the following program, we will use this formula to find the sum.

main.swift

``````import Foundation

var n = 10
var sum = n*(n+1)/2

print("The sum of first \(n) natural numbers is \(sum)")``````

Program Output

``The sum of first 10 natural numbers is 55``

## Summary

Summarising this tutorial, we learned how to find the sum of first n Natural Numbers using for loop or formula.