Write a recursive function to calculate the sum of digits of an integer 

write a recursive function that accepts an integer and finds sum of its digits , as example sum(2370) will print 12

solution

	#include <stdio.h>
	#include <math.h>
	int sumofdigits(int n)
	{
	int sum=0;
	if(n>0)
	{
	sum=(n%10)+sumofdigits(n/10);
	}
	return(sum);
	}
	int main()
	{
	int number;
	printf("Enter positive integer\n");
	scanf("%d",&number);
	if(number>0)
	{
	printf("sum of digits of %d = %d",number,sumofdigits(number));
	}
	else
	{
	printf("Error! you must enter a positive integer");
	}
	return 0;
	}

view raw sumofdigits.c hosted with ❤ by GitHub