I got this error every time I compiler operator-(): "error C2804: binary 'operator +' has too many parameters" class Fraction { public: Fraction () { num = 0; deno = 0, result = 0;}; Fraction(int x, int y) { num = x, deno = y;}; Fraction operator +(Fraction& x, Fraction& y); //this line generates the above erro void menu(); double num, deno, result; };

Your overload of the + operator would be perfectly fine if it was defined outside the class (as that requires two parameters). Within a class definition, the left-hand-side operand is already assumed to be 'this', so only the right-hand-side operand can be specified as a singular parameter. You can either move the function outside the class, or remove one of the parameters in the member function. Cheers