OOP-RMMP complie method move directory cd src complie (in /src) g++ main.cpp ./admin/admin.cpp ./admin/admin.h ./database/DataBase.cpp ./database/DataBase.h ./room/room.cpp ./room/room.h ./student/student.cpp ./student/student.h ./user/User.cpp ./user/User.h -o test -std=c++14 std::make_unique realted uniuqe_ptr can surpport in c++14 So, please Compile to C++14 Login Infomation Admin Login ID : mw412 PASSWORD : pww12 Student Login / Sign Up if you don't want to create new account, you can login this. ID : coca PASSWORD : pepsi