This class implements function which can be used in ICalculator to calculate sign of the argument. Return -1 if argument is negative. Return 1 if argument is positive. Return 0 if argument is 0.

You can find more information in comments below. Overrided methods can be found in corresponding base class or interface.

class CProcedureSign :public CProcedure
    {
    public:
        CVariable *Calculate(CVariable *parent, CVariable *args) override;
    
        CProcedureSign();
    };