Example: C++ Program to Find Sum of Natural Numbers using Recursion

C
C++
C#
Java
Python
PHP

// C++ Program to Find Sum of Natural Numbers using Recursion
#include <bits/stdc++.h>
using namespace std;
int recSum(int x);

// It's the driver function
int main() {
    int x;
    // x - denotes a positive number

    cout << "-----Enter a positive number to get the sum-----\n";
    cin >> x;

    cout << "\nThe Sum is: " << recSum(x) << "\n";
    return 0;
}

// It's the recrsive function
// To make the sum of natural numbers
int recSum(int n) {
    if (n)
        return n + recSum(n - 1);
    else
        return n;
}