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# Python Program to Find Sum of First N Natural Numbers

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. Itâ€™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:

1. It defines a function called `calculate_sum` that takes an integer `n` as input.
2. Inside the `calculate_sum` function, it initializes a variable `sum` to 0. This variable will store the sum of the natural numbers.
3. It uses a `for` loop with the `range()` function to iterate from 1 to `n+1`. The loop variable `i` represents each natural number.
4. Within each iteration of the loop, it adds the current value of `i` to the `sum` variable.
5. After the loop completes, it returns the final value of `sum`.
6. The program prompts the user to enter a positive integer `N` using the `input()` function.
7. It converts the user input to an integer using the `int()` function and assigns it to the variable `n`.
8. It calls the `calculate_sum` function with the value of `n` as an argument and assigns the result to the variable `result`.
9. Finally, it prints the sum of the first N natural numbers using a formatted string, combining the value of `n` and `result`.

## Input/ Output

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