#include "calc.hpp" #include <iostream> int main() { std::string user_input; std::cin >> user_input; if (user_input.empty()) { std::cout << "Empty input\n"; return 1; } std::cout << "User input is \"" << user_input << "\"\n"; const int result{evaluate(user_input)}; std::cout << "Result is: " << result << '\n'; }