inheritance - Derived Class C++ -

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• what weird colon-member (“ : ”) syntax in constructor? 12 answers

i know can stupid don't know how name question. i'm non native english. learn c++ book , there program shows name , pay rate of employee (base class) , manager (derived class) added bool variable salaried. here source code:

//base class class employee { private:     string name;     double pay; public:     employee() {         name = "";         pay = 0;     }      employee(string empname, double payrate) {         name = empname;         pay = payrate;     }      string getname() const {         return name;     }      void setname(string empname) {         name = empname;     }      double getpay() const {         return pay;     }      void setpay(double payrate) {         pay = payrate;     }      string tostring() {         stringstream stm;         stm << name << ": " << pay;         return stm.str();      } };  //derived class class manager : public employee { private:     bool salaried; public:     manager(string name, double payrate, bool issalaried)         :employee(name, payrate)     {         salaried = issalaried;     }     bool getsalaried() {         return salaried;     } };  int main() {     employee emp1("mary smith", 15.00);     cout << "employee name: " << emp1.getname() << endl;     cout << "employee pay rate: " << emp1.getpay() << endl;     manager emp2("bob brown", 1500, true);     cout << "employee name: " << emp2.getname() << endl;     cout << "employee pay rate: " << emp2.getpay() << endl;     cout << "is salaried: " << emp2.getsalaried() << endl;     return 0; } 

can explain me why part

:employee(name, payrate) 

must added code work properly?

the part

:employee(name, payrate) 

you mention used call constructor

employee(string empname, double payrate) 

of base class employee before executing body of constructor

manager(string name, double payrate, bool issalaried) 

of derived class manager.