/in/foo.cc: In member function 'int Trapezoid::check()':
/in/foo.cc:64:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^
/in/foo.cc: In member function 'int Parallelogram::check()':
/in/foo.cc:86:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^
/in/foo.cc: In member function 'int Rectangle::check()':
/in/foo.cc:108:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^
/in/foo.cc: In member function 'int Square::check()':
/in/foo.cc:129:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^