You need to fill some fields in src/long_poll/metadata.hpp:
...std::string yandex_key
= "your Yandex API key";
...std::string access_token
= "your group token";
...std::string user_token
= "your user token";
...std::string group_id
= "id of your group";
...int admin_id
= your user id;
...std::string api_version
= "5.80";
...std::string logfile
= "/path/to/logfile";
...std::string errfile
= "/path/to/errfile";
Next please do in cpp_vk_bot directory:
make