sum-of-natural-numbers-recursion.c

#include <stdio.h>
int sum(int n);
int main()
{
    int n;
    printf("enter natural number : ");
    scanf("%d",&n);
    printf("%d",sum(n)); 
    return 0;
}

    int sum(int n)
    {
     if (n!=0)
     {
        return n + sum(n-1);
     }  
        else 
        return n;
    }