C++ and Python Programs for Even/Odd and Sum of N Natural Numbers

Check if a Number is Even or Odd in C++

Given an integer input, the objective is to determine whether a number is even or odd using C++ programming.

An even number is completely divisible by 2, whereas an odd number leaves a remainder of 1 when divided by 2.

Sum of First N Natural Numbers (C++ and Python)

Natural numbers are a sequence of positive numbers starting from 1. The sum of the first N natural numbers can be calculated using different methods.

Method 1: Using for Loop (C++)

#include 
using namespace std;
int main() {
    int Number, Sum = 0;
    cout << "\n Kindly Insert an Integer Variable\n";
    cin >> Number;
    for(int i = 1; i <= Number; i++)
    {
         Sum = Sum + i;
    }
    cout << "Sum of Natural Numbers = " << Sum;
    return 0;
}
            

Output:

Kindly Insert an Integer Variable : 3 
Sum of Natural Numbers = 6

Method 2: Using for Loop (Python)

n = int(input("Kindly Insert an Integer Variable: "))
sum = 0
for i in range(1, n + 1):
    sum += i
print("Sum of Natural Numbers =", sum)
            

Output:

Kindly Insert an Integer Variable: 3 
Sum of Natural Numbers = 6

Method 3: Using Formula (Python)

n = int(input("Kindly Insert an Integer Variable: "))
sum = n * (n + 1) // 2
print("Sum of Natural Numbers =", sum)
            

Output:

Kindly Insert an Integer Variable: 3 
Sum of Natural Numbers = 6

Method 4: Using Recursion (Python)

def getSum(n):
    if n == 0:
        return 0
    return n + getSum(n - 1)

n = int(input("Kindly Insert an Integer Variable: "))
print("Sum of Natural Numbers =", getSum(n))
            

Output:

Kindly Insert an Integer Variable: 3 
Sum of Natural Numbers = 6