如何为类中的常量赋值

#include <string>
#include <iostream>
using namespace std;

class A{
    const string name;
    public:
        A(const string& id=""):name(id){}
        ~A(){}
        void print(){
            cout << name<<endl;
        }

};

class B{
    string name;
    public:
        B(const string id){name=id;}
        ~B(){}
        void print(){
            cout << name<<endl;
        }

};
int main(){
    A aa("aa");
    aa.print();
    B bb("bb");
    bb.print();
}