narcissistic numbers

narci.cc

#include <vector>
#include <math.h>

namespace number {
    bool is_narci(int num) {
        int num_cp = num;
        int num_length = num == 1 ? 1 : ceil(log10(num));
        int length = num_length;
        int acc = 0;

        while (length != 0) {
            double reduce =
                (num % (int)pow(10, num_length)) == 0 ? 0 : 1;
            int base = pow(10, (length - reduce));
            int diff = (num_cp / base);
            acc += pow(diff, num_length);
            num_cp -= (diff * base);
            length -= 1;
        }

        return num == acc;
    }
}