base call virtual, C++ (vc++)

base call virtual

#include <iostream>
#include <cstdlib>
#include <iostream>
#include <chrono>
#include <vector>
class A{
    public: int randomNumber=((double) rand() / (RAND_MAX))*10;
    public: virtual int f(){return randomNumber*3;};
    public: virtual int g(){return randomNumber*3;};
    public:  int fa(){return randomNumber*3;};
};
class B  final: public A {
    public: virtual int f(){return randomNumber*4;};

};
class C  : public A {
    public: virtual int f()final{return randomNumber*4;};
    public: virtual int g(){return randomNumber*5;};
};
int main(){
    std::vector<A*> as;
    std::vector<B*> bs;
    std::vector<C*> cs;
    const int numTest=10000;
    for(int n=0;n<numTest;n++){
        as.push_back(new A());
        bs.push_back(new B());
        cs.push_back(new C());
    };
    int accu=0;
    for(int n=0;n<numTest;n++){
        accu+=as[n]->f();  //note: warm up
    };
    auto t1= std::chrono::system_clock::now();
    for(int n=0;n<numTest;n++){
        accu+=as[n]->f();  //test 1 : base class - virtual function
    };
    auto t2= std::chrono::system_clock::now();
    for(int n=0;n<numTest;n++){
        accu+=bs[n]->f();  //test 2: derived class (final at class-level)
    };
    auto t3= std::chrono::system_clock::now();
    for(int n=0;n<numTest;n++){
        accu+=cs[n]->f();  //test 3: derived function (with final)
    };
    auto t4= std::chrono::system_clock::now();
    for(int n=0;n<numTest;n++){
        accu+=cs[n]->g();  //test 4: derived function (w/o final)
    };
    auto t5= std::chrono::system_clock::now();
    auto t21=t2-t1;
    auto t32=t3-t2;
    auto t43=t4-t3;
    auto t54=t5-t4;
     std::cout<<"test1="<<t21.count()<<std::endl;    
     std::cout<<"test2="<<t32.count()<<std::endl;
     std::cout<<"test3="<<t43.count()<<std::endl;
     std::cout<<"test4="<<t54.count()<<std::endl;
     std::cout<<"forbid optimize"<<accu;
}


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