C Program for the Difference between sums of odd and even digits?

Given a number, find the difference between sum of odd digits and sum of even digits. Which means we will be count all even digits and all odd digits and the subtracting their sums.

Sample

Input:12345
Output:3

Explanation

the odd digits is 2+4=6
the even digits is 1+3+5=9
odd-even=9-6=3

Taking every digit out of number and checking whether the digit is even or odd if even then add it to even sum if not then to odd sum and then take difference of them.

Example

#include <iostream>
using namespace std;
int main() {
   int n, r=0;
   int diff =0;
   int even=0;
   int odd=0;
   n=12345;
   while(n != 0){
      r = n%10;
      if(r % 2 == 0) {
         even+=r;
      } else {
         odd+=r;
      }
      n/=10;
   }
   diff=odd-even;
   printf("%d",diff);
   return 0;
}