View Compilation Error

0_0_31187467_15446.cpp:69:16: error: 'operato' is neither function nor member function; cannot be declared friend
    friend bool operato
                ^
0_0_31187467_15446.cpp:69:16: error: expected ';' at end of member declaration
0_0_31187467_15446.cpp:69:16: error: expected '}' at end of input
0_0_31187467_15446.cpp:69:16: error: expected unqualified-id at end of input
0_0_31187467_15446.cpp:69:16: error: expected '}' at end of input