cflxl

#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cmath>
#include <cstdlib>
#include <time.h>

using namespace std;

template <typename T>
void output(const T &obj)
{
    for (auto item : obj)
    {
        cout << item << " ";
    }
    cout << endl;
}

int main()
{
    vector<int> v1{1, 9, 8, 4};
    v1.insert(v1.begin(), 2022);
    v1.insert(v1.end(), 2023);
    cout << "v1: ";
    output(v1);
    v1.pop_back();
    v1.erase(v1.begin());
    cout << "v1: ";
    output(v1);
    vector<string> v2{"《1984》", "《動(dòng)物農(nóng)場(chǎng)》", "《美麗新世界》"};
    cout << "v2: ";
    output(v2);
    return 0;
}

#include <iostream>
using std::cout;
using std::endl;

class Point
{
public:
    Point(int x0 = 0, int y0 = 0);
    Point(const Point &p);
    ~Point() = default;

    int get_x() const { return x; }
    int get_y() const { return y; }
    void show() const;

private:
    int x, y;
};

Point::Point(int x0, int y0) : x{x0}, y{y0}
{
    cout << "copy constructor called." << endl;
}

Point::Point(const Point &p) : x{p.x}, y{p.y}
{
    cout << "copy constructor called." << endl;
}

void Point::show() const
{
    cout << "(" << x << "," << y << ")" << endl;
}

int main()
{
    Point p1(3, 4);
    p1.show();

    Point p2 = p1;
    p2.show();

    Point p3{p2};
    p3.show();
    cout << p3.get_x() << endl;
}

#include <iostream>
#include <iomanip>

using std::cout;
using std::endl;

class Clock
{
public:
    Clock(int h = 0, int m = 0, int s = 0);
    Clock(const Clock &t);
    ~Clock() = default;

    void set_time(int h, int m = 0, int s = 0);

    void show_time() const;

private:
    int hour, minute, second;
};

Clock::Clock(int h, int m, int s) : hour{h}, minute{m}, second{s}
{
    cout << "constructor called" << endl;
}

Clock::Clock(const Clock &t) : hour{t.hour}, minute{t.minute}, second{t.second}
{
    cout << "constructor called" << endl;
}

void Clock::set_time(int h, int m, int s)
{
    hour = h;
    minute = m;
    second = s;
}

void Clock::show_time() const
{
    using std::setfill;
    using std::setw;

    cout << setfill('0') << setw(2) << hour << ":" << setw(2) << minute << ":" << setw(2) << second << endl;
}

Clock reset()
{
    return Clock(0, 0, 0);
}

int main()
{
    Clock c1(11, 1, 6);
    c1.show_time();
    c1 = reset();
    c1.show_time();
    Clock c2(c1);
    c2.set_time(6);
    c2.show_time();
}

#include <iostream>

class X
{
public:
    X();
    ~X();
    X(int m);
    X(const X &obj);
    X(X &&obj)
    noexcept;
    void show() const;

private:
    int data;
};

X::X() : data{42}
{
    std::cout << "default constructor called.\n";
}

X::~X()
{
    std::cout << "destructor called.\n";
}

X::X(int m) : data{m}
{
    std::cout << "constructor called.\n";
}

X::X(const X &obj) : data{obj.data}
{
    std::cout << "copy constructor called.\n";
}

X::X(X &&obj) noexcept : data{obj.data}
{
    std::cout << "move constructor called.\n";
}

void X::show() const
{
    std::cout << data << std::endl;
}

int main()
{
    X x1;
    x1.show();

    X x2{2049};
    x2.show();

    X x3{x1};
    x3.show();

    X x4{std::move(x2)};
    x4.show();
}

#include <iostream>
#include <iomanip>

using namespace std;

class Rectangle
{
public:
    Rectangle();
    Rectangle(int l, int w);
    Rectangle(const Rectangle &x);

    double len();
    double wide();
    double area();
    double circumference();
    void resize(double times);
    void resize(double l_times, double w_times);
    ~Rectangle() = default;

public:
    double length, width;
};

Rectangle::Rectangle()
{
    length = 2.0;
    width = 1.0;
}

Rectangle::Rectangle(int l, int w)
{
    length = l;
    width = w;
}

Rectangle::Rectangle(const Rectangle &x)
{
    length = x.length;
    width = x.width;
}

double Rectangle::len()
{
    return length;
}

double Rectangle::wide()
{
    return width;
}

double Rectangle::area()
{
    return length * width;
}

double Rectangle::circumference()
{
    return length * 2 + width * 2;
}

void Rectangle::resize(double times)
{
    length *= times;
    width *= times;
}

void Rectangle::resize(double l_times, double w_times)
{
    length *= l_times;
    width *= w_times;
}

void output(const Rectangle &rect)
{
    Rectangle res = rect;
    cout << "矩陣信息：\n";
    cout << fixed << setprecision(2);
    cout << "長：     " << res.len() << endl;
    cout << "寬：     " << res.wide() << endl;
    cout << "面積：   " << res.area() << endl;
    cout << "周長：   " << res.circumference() << endl;
}

int main()
{
    Rectangle rect1;
    output(rect1);

    Rectangle rect2(10, 5);
    output(rect2);

    Rectangle rect3(rect1);
    rect3.resize(2);
    output(rect3);

    rect3.resize(5, 2);
    output(rect3);

    return 0;
}