实验1 类和对象

实验任务1-1

#include <iostream>
#include <string>
#include <vector>

int main()
{
using namespace std;

string s1; 
string s2{"A B C"}; 
string s3{s2}; 
string s4 = s2; 

s1 = "123";

vector<string> v1;
v1.push_back(s1); 
v1.push_back(s2 + "a");
v1.push_back(s3 + "b");
v1.push_back(s4 + "c");

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;
}

 

实验任务1-2

#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, 2, 3, 4};
v1.insert(v1.begin(), 1111); 
v1.insert(v1.end(), 2222); 

cout << "v1: ";
output(v1);

v1.pop_back();
v1.erase(v1.begin());
cout << "v1: ";
output(v1);

vector<string> v2{"《零年1945》", "《Il nome della rosa》", "《梦的解析》"};
cout << "v2: ";
output(v2);
}

 

实验任务2

#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;
}

 

实验任务3

#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(12, 0, 0); 
}

int main()
{
Clock c1(23, 30, 55);
c1.show_time();

c1 = reset();
c1.show_time();

Clock c2(c1); 
c2.set_time(9);
c2.show_time();
}

 

任务实验4

#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();
}

第一次调用默认构造函数X()

第二次调用构造函数X(int m)

第三次调用复制构造函数X(const X& obj)

第四次调用移动构造函数X(X&& OBJ) noexcept

之后调用四次析构函数~X()

 

实验任务5

#include"stdafx.h"
#include <iostream>
#include <iomanip>

class Rectangle{
public:    
    float length;
    float width;
    Rectangle();
    Rectangle(float l, float w);
    Rectangle(const Rectangle& rect);
    ~Rectangle() ;
    float len();
    float wide();
    float area() ;
    float circumference() ;
    void resize(int times);
    void resize(int l_times,int w_times);

    void output( Rectangle& rect);
};


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

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

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

Rectangle::~Rectangle() {

}

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

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

float Rectangle::area() {
    return length * width;

}

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

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

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


void output( Rectangle &rect) {
    using namespace std;

    cout << "矩形信息: \n";
    cout << fixed << setprecision(2);
    cout << left << setw(6) << "长：" << rect.length << endl
        << setw(6) << "宽：" << rect.width << endl
        << setw(6) << "面积：" << rect.area() << endl
        << setw(6) << "周长：" << rect.circumference() << endl << 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);
    }