实验4 类的继承、派生和多态

1.车辆基本信息管理

#include <iostream>
using namespace std;

#include "car.h"
#include "electricCar.h" 

int main() {
    // 测试Car类 
    Car oldcar("Audi", "a4", 2016);
    cout << "--------oldcar's info--------" << endl;
    oldcar.updateOdometer(25000);
    cout << oldcar << endl;

    // 测试ElectricCar类 
    ElectricCar newcar("Tesla", "model s", 2016);
    newcar.updateOdometer(2500);
    cout << "\n--------newcar's info--------\n";
    cout << newcar << endl;

    system("pause");

    return 0;
}

main.cpp

#ifndef BATTERY_H
#define BATTERY_H
class Battery {
public:
    Battery(int size = 70);
    int rebattery();
    int batterySize;
};
#endif

battery.h

#include"battery.h"

Battery::Battery(int size) {
    batterySize = size;
}
int Battery::rebattery() {
    return batterySize;
}

battery.cpp

#ifndef CAR_H
#define CAR_H
#include<iostream>
#include<string>
using namespace std;
class Car {
public:
    Car(string maker0, string model0, int year0, int odometer0 = 0) :maker(maker0), model(model0), year(year0), odometer(odometer0) {}
    friend ostream& operator<<(ostream &out, const Car &c);
    void updateOdometer(int o2);
    string maker, model;
    int year, odometer;
};
#endif

car.h

#include"car.h"
#include<string>
#include<iostream>
using namespace std;

ostream& operator<<(ostream &out, const Car &c) {
    out << "maker:" << c.maker << endl << "moder:" << c.model << endl << "year:" << c.year << endl << "odometer:" << c.odometer << endl;
    return out;
}
void Car::updateOdometer(int o2) {
    if (o2 < odometer) cout << "the number is wrong" << endl;
    else odometer = o2;
}

car.cpp

#ifndef ELECTRICCAR_H
#define ELECTRICCAR_H
#include"battery.h"
#include"car.h"
#include<iostream>
#include<string>
class ElectricCar :public Car, public Battery {
public:
    ElectricCar(string maker1, string model1, int year1, int odometer1 = 0, int size1 = 70) :Car(maker1, model1, year1, odometer1), Battery(size1) {}
    friend ostream& operator<<(ostream &outCar, const ElectricCar &e);
    void updateOdometer(int o2);
};
#endif

electricCar.h

#include"electricCar.h"
#include"battery.h"
#include"car.h"
#include<iostream>
using namespace std;

ostream& operator<<(ostream &out, const ElectricCar &e) {
    out << "maker:" << e.maker << endl << "moder:" << e.model << endl << "year:" << e.year << endl << "odometer:" << e.odometer << endl << "batterysize:" << e.batterySize << "-kwh" << endl;
    return out;
}
void ElectricCar::updateOdometer(int o2) {
    if (o2 < odometer) cout << "the number is wrong" << endl;
    else odometer = o2;
}

electricCar.cpp

2. 补足程序，重载运算符[]为一维动态整形数组类ArrayInt的成员函数，使得通过动态整形数组对象名和下标可以
访问对象中具体元素。

#include <iostream>
using namespace std;

#include "arrayInt.h"

int main() {
    // 定义动态整型数组对象a，包含2个元素，初始值为0
    ArrayInt a(2);
    a.print();

    // 定义动态整型数组对象b，包含3个元素，初始值为6
    ArrayInt b(3, 6);
    b.print();

    // 通过对象名和下标方式访问并修改对象元素
    b[0] = 2;
    cout << b[0] << endl;
    b.print();

    system("pause");

    return 0;
}

main.cpp

#ifndef ARRAY_INT_H
#define ARRAY_INT_H

class ArrayInt {
public:
    ArrayInt(int n, int value = 0);
    ~ArrayInt();
    // 补足:将运算符[]重载为成员函数的声明
    // ×××
    int &operator[](int a);
    void print();
private:
    int *p;
    int size;
};

#endif

arrayInt.h

#include "arrayInt.h"
#include <iostream>
#include <cstdlib>
using std::cout;
using std::endl;

ArrayInt::ArrayInt(int n, int value) : size(n) {
    p = new int[size];

    if (p == nullptr) {
        cout << "fail to mallocate memory" << endl;
        exit(0);
    }

    for (int i = 0; i < size; i++)
        p[i] = value;
}

ArrayInt::~ArrayInt() {
    delete[] p;
}

void ArrayInt::print() {
    for (int i = 0; i < size; i++)
        cout << p[i] << " ";
    cout << endl;
}

// 补足:将运算符[]重载为成员函数的实现
// ×××
int& ArrayInt:: operator[](int a)
{
    return p[a];
}

arrayInt.cpp

实验总结：

1.第一题做了很久，最后还是在同学的指导下完成的，说明这方面的知识不是很懂；

2.第二题已经给好了程序框架，只要填上两句就好了。