C program that prompts the user for a positive integer and then computes the sum of all the digits of the number
Posted by Samath
Last Updated: May 04, 2016
  2730

Write a program (addDigits.c) that prompts the user for a positive integer and then computes the sum of all the digits of the number. For example, if the user enters 2784, then the program reports 21. If the user enters 59, then the program reports 14. The program should work for any number having one to ten digits.

Solution:

#include <stdio.h>
int main(int argc, char *argv[])
{
	int num=0;
	int sum=0;
	int sep=0;
	printf("Please enter a positive integer: ");
	scanf("%d",&num);

	while(num > 0)
	{
		sep = num%10;
		num = num/10;
		sum = sum + sep;
	}
	
	printf("Result: %d\n",sum);
	return 0;
}