5月21日打卡

例5-3

题目： 具有静态、动态生存期对象的时钟程序。

代码部分

#include<iostream>
using namespace std;
class Clock {
public:
    Clock():hour(0),minute(0),second(0){}
    void setTime(int a=0, int b=0, int c=0)
    {
        hour = a;
        minute = b;
        second = c;
    }
    void showTime()
    {
        cout << hour << ":" << minute << ":" << second << endl;
    }
private:
    int hour, minute, second;
};
Clock globClock;
int main()
{
    cout << "First time output:" << endl;
    globClock.showTime();
    globClock.setTime(8, 30, 30);
    Clock myClock(globClock);
    cout << "Second time output:" << endl;
    myClock.showTime();
    return 0;
}

例5-4

题目：具有静态数据成员的Poin类

代码部分：

#include<iostream>
using namespace std;
class Point {
private:
    int x, y;
    static int count;
    constexpr static int origin = 0;
public:
    Point(int x = 0, int y = 0) :x(x), y(y) { count++; }
    Point(Point& p)
    {
        x = p.x;
        y = p.y;
        count++;
    }
    ~Point() { count--; }
    int getX() { return x; }
    int getY() { return y; }
    void showCount() {
        cout << " Object count=" << count << endl;
    }
    

};
int Point::count = 0;
constexpr int Point::origin = 0;
int main()
{
    Point a(4, 5);
    cout << "Point A:" << a.getX() << "," << a.getY();
    a.showCount();
    Point b(a);
    cout << "Point B:" << b.getX() << "," << b.getX();
    b.showCount();
    return 0;
}