[C++应用程序性能优化]单继承

class simpleClass{public: static int n_count; int n_value; char c; simpleClass() { printf("Create base class.\n"); } virtual ~simpleClass() { printf("Destroy base class.\n"); } int get_value(void); virtual void foo(void) { printf("foo in base class.\n"); } static void add_count();};class dsimpleClass : public simpleClass{public: int n_sub_value; dsimpleClass() { printf("create derived class.\n\n"); } ~dsimpleClass() { printf("destroy derived class.\n"); } virtual void foo() { printf("foo in derived class.\n"); }};#include <stdlib.h>#include <stdio.h>#include "gtest.h"int simpleClass::n_count = 0;int main(){ dsimpleClass asimple; printf("Object start address: %x\n", &asimple); printf("n_value address: %x\n", &asimple.n_value); printf("c address: %x\n", &asimple.c); printf("n_subvalue address: %x\n", &asimple.n_sub_value); printf("base class size: %d ; derived class size: %d\n\n", sizeof(simpleClass), sizeof(dsimpleClass)); system("pause"); return 0;}