View Compilation Error

0_0_21600521_4021.cpp:98:16: error: stray '#' in program
   return ch - 'a' ;
                ^
0_0_21600521_4021.cpp:98:22: error: stray '#' in program
   return ch - 'a' ;
                      ^
0_0_21600521_4021.cpp: In member function 'int Trie::Get(type_buf)':
0_0_21600521_4021.cpp:98:17: error: lvalue required as unary '&' operand
   return ch - 'a' ;
                 ^
0_0_21600521_4021.cpp:98:20: error: 'a' was not declared in this scope
   return ch - 'a' ;
                    ^