/tmp/cc5z2D0T.o: In function `commandThread(void*)':
Server.cpp:(.text+0x30d): undefined reference to `Client::Client(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, ChatRoom*)'
/tmp/cc5z2D0T.o: In function `main':
Server.cpp:(.text+0x571): undefined reference to `ChatRoom::ChatRoom(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >)'
/tmp/cc5z2D0T.o: In function `ClientCollection::findClient(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)':
Server.cpp:(.text._ZN16ClientCollection10findClientESs[ClientCollection::findClient(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)]+0x33): undefined reference to `Client::getID()'
collect2: ld returned 1 exit status