View Compilation Error

0_0_27438399_25240.cpp: In member function 'void Bitree::fun()':
0_0_27438399_25240.cpp:48:22: error: template argument 1 is invalid
         stack<*Binode> s;
                      ^
0_0_27438399_25240.cpp:48:22: error: template argument 2 is invalid
0_0_27438399_25240.cpp:48:25: error: invalid type in declaration before ';' token
         stack<*Binode> s;
                         ^