Error(s):

source_file.cpp: In member function ‘void vertex::translate(const vector&)’:
source_file.cpp:7:10: error: ‘float xyz::x’ is protected
    float x,y,z;
          ^
source_file.cpp:23:17: error: within this context
       x += vect.x;
                 ^
source_file.cpp:7:12: error: ‘float xyz::y’ is protected
    float x,y,z;
            ^
source_file.cpp:24:17: error: within this context
       y += vect.y;
                 ^
source_file.cpp:7:14: error: ‘float xyz::z’ is protected
    float x,y,z;
              ^
source_file.cpp:25:17: error: within this context
       z += vect.z;
                 ^