/in/ex6.cpp: In member function 'BinaryTree& BinaryTree::operator=(const BinaryTree&)':
/in/ex6.cpp:25:1: error: control reaches end of non-void function [-Werror=return-type]
 }
 ^
cc1plus: all warnings being treated as errors
/in/compile/Makefile:24: recipe for target 'ex6.o' failed
make: *** [ex6.o] Error 1