1、思维导图

https://www.zhixi.com/view/9e899ee0

2、作业

#include <iostream>

using namespace std;

class Rect
{
    int width;
    int height;
public:
    void init(int w,int h);//初始化函数
    void set_w(int w);//更改宽度
    void set_h(int h);//更改高度
    void show();//输出矩形周长和面积
};

void Rect::init(int w,int h)
{

    this -> width = w;
    this -> height = h;
}

void Rect::set_w(int w)
{
    this -> width = w;
}

void Rect::set_h(int h)
{
    this -> height = h;
}

void Rect::show()
{
    int llong,aarea;
    llong=2*(this->width + this->height);
    aarea=(this->width)*(this->height);
    cout << "长方形周长为：" << llong << endl;
    cout << "长方形面积为：" << aarea << endl;
}

int main()
{
    Rect s1;
    s1.init(5,10);
    s1.show();
    return 0;
}