Sum of two digits by recursion | C program

#include<stdio.h>
int so(int);

int main()
{
 int i;
 printf(" Enter any number : ");
 scanf("%d",&i);
 printf("Sum of digit are : %d",so(i));
 return 0;
}

int so(int n)
{
 if(n<1)
  return 0;
 return(n%10+so(n/10));
}

Bhuvan Arora