实验1

#include <iostream>
#include <string>
#include <vector>
int main()
{
    using namespace std;
    string s1; 
    string s2{"c plus plus"}; 
    string s3{s2}; 
    string s4 = s2; 
    s1 = "oop";
    vector<string> v1; 
    v1.push_back(s1); 
    v1.push_back(s2 + "1");
    v1.push_back(s3 + "2");
    v1.push_back(s4 + "3");

    cout << "output1: " << endl;
    for(auto item: v1)
    cout << item << endl;

    cout << "ouput2: ";
    for(auto p = v1.begin(); p != v1.end(); ++p)
    cout << *p << endl;

    cout << "output3: " << endl;
    for(auto i = 0; i < v1.size(); ++i)
    cout << v1[i] << endl;
    vector<string> v2{v1.rbegin(), v1.rend()}; 

    cout << "v2: " << endl;
    for(auto item: v2)
    cout << item << endl;
}    

#include<iostream>
#include<string>
#include<vector>
#include<cmath>
#include<cstdlib>
#include<time.h>
template<typename T>
void output(const T& obj) 
{
    for(auto item: obj)
    std::cout << item << " ";
    std::cout << std::endl;
}
int main()
{
    using namespace std;
    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》", "《动物农场》", "《美丽新世界》"};
    cout << "v2: ";
    output(v2);
}

#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 << "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(4, 5); 
    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 << "copy 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::setw;
    using std::setfill;
    cout << setfill('0') << setw(2) << hour << ":"
    << setw(2) << minute << ":"
    << setw(2) << second << endl;
}

Clock reset() {
return Clock(0, 0, 0); 
}
int main()
{
    Clock c1(12, 0, 5); 
    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();
}