Call a function (ofstream) C++ -

hello have probleme code.i don't know how call function ofstream.

//username username(ofstream& reg); //password password(ofstream& reg); //email email(ofstream& reg); //gender gender(ofstream& reg); 

line(22) error is: expected primary-expression before '&' token line(24) error is: expected primary-expression before '&' token line(26) error is: expected primary-expression before '&' token line(28) error is: expected primary-expression before '&' token 

remove ofstream &. function calls don't include types.