암스트롱 번호를 확인하는 C 프로그램?

Input:370
Output:370 is an Armstrong Number

370 = 3*3*3 + 7*7*7 + 0*0*0
= 27 + 343 + 0
= 370

include <iostream>
using namespace std;
int main() {
   int n, num, rem, sum = 0;
   cin >> n;
   num = n;
   while(num != 0) {
      digit = num % 10;
      sum += digit * digit * digit;
      num /= 10;
   }
   if(sum == n)
      printf("%d is an Armstrong number.", n );
   else
      printf("%d is not an Armstrong number.",n);
   return 0;
}