C Program to Find Sum of Natural Numbers using Recursion

In this program, user is asked to enter a positive integer and sum of natural numbers up to that integer is displayed by this program. Suppose, user enters 5 then,

Sum will be equal to 1+2+3+4+5 = 15

#include<stdio.h>

#include<conio.h>

int sum(int);

void main()

{

    int n;

    printf("Enter number: ");

    scanf("%d",&n);

    printf("Sum of natural numbers up to %d is %d",n,sum(n));

    getch();

}

int sum(int n)

{

    if(n!=0)

        return n+sum(n-1);    /*recursion used*/

}

OUTPUT:

C Program to Calculate Factorial of a Number Using Recursion >>