This Python program calculates the sum of the first N natural numbers. It defines a function called `calculat_sum`

that takes an integer `n`

as input and uses a `for`

loop to iterate from 1 to `n`

, adding each number to the sum. The program then prompts the user to enter a positive integer `n`

, calls the `calculate_sum`

function, and prints the result. It’s important to note that the program assumes the user will provide a positive integer as input.

## Problem Statement

Write a Python program that calculates the sum of the first N natural numbers.

Inputs:

- An integer N representing the count of natural numbers to be considered.

Output:

- The sum of the first N natural numbers.

## Python Program to Find Sum of First N Natural Numbers

def calculate_sum(n): sum = 0 for i in range(1, n + 1): sum += i return sum # Example usage n = int(input("Enter a positive integer: ")) result = calculate_sum(n) print(f"The sum of the first {n} natural numbers is {result}.")

## How it Works

The Python program to calculate the sum of the first N natural numbers works as follows:

- It defines a function called
`calculate_sum`

that takes an integer`n`

as input. - Inside the
`calculate_sum`

function, it initializes a variable`sum`

to 0. This variable will store the sum of the natural numbers. - It uses a
`for`

loop with the`range()`

function to iterate from 1 to`n+1`

. The loop variable`i`

represents each natural number. - Within each iteration of the loop, it adds the current value of
`i`

to the`sum`

variable. - After the loop completes, it returns the final value of
`sum`

. - The program prompts the user to enter a positive integer
`N`

using the`input()`

function. - It converts the user input to an integer using the
`int()`

function and assigns it to the variable`n`

. - It calls the
`calculate_sum`

function with the value of`n`

as an argument and assigns the result to the variable`result`

. - Finally, it prints the sum of the first N natural numbers using a formatted string, combining the value of
`n`

and`result`

.

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