#include <iostream>
int main() {
    int n{5};
    if (n < 0) {
        std::cout << "invalid\n";
        return 1;
    } else if (n == 0) {
        std::cout << "zero\n";
    } else {
        if (n % 2 == 0) {
            std::cout << "even\n";
        } else {
            std::cout << "odd\n";
        }
    }
    std::cout << "done\n";
    return 0;
}