P21895: Nombres estrobogramàtics

#include <iostream>
#include <vector>
using namespace std;


int count_digits(int n) {
    int dig = 0;
    while (n != 0) {
        n = n/10;
        ++dig;
    }
    return dig;
}

bool es_estrobogramatic(int n) {
    if (n < 10) {
        if (n == 1 or n == 0 or n == 8) return true;
        return false;
    }
    else {
        int digits = count_digits(n);
        vector<int> estrobo(digits);
        for (int i = digits-1; i >= 0; --i) {
            if (n%10 == 2 or n%10 == 3 or n%10 == 4 or n%10 == 7) return false;
            estrobo[i] = n%10;
            n = n/10;
        }
        int i = 0;
        int j = digits-1;
        while (i <= j) {
            if (estrobo[i] == estrobo[j] && (estrobo[i] == 0 or estrobo[i] == 1 or estrobo[i] == 8));
            else if ((estrobo[i] == 6 && estrobo [j] == 9) or (estrobo[i] == 9 && estrobo[j] == 6));
            else return false;
            ++i;
            --j;
        }
        return true;
    }
}


int main() {
    int n;
    int count_senar = 0;
    while (cin >> n) {
        if (es_estrobogramatic(n)) cout << n << " si es estrobogramatic" << endl;
        else if (not es_estrobogramatic(n)) cout << n << " no es estrobogramatic" << endl;
        if (es_estrobogramatic(n) && n%2 != 0) ++count_senar;
    }
    cout << endl << "estrobogramatics senars: " << count_senar << endl;
}