实验1 类和对象

 

#include <iostream>

#include <string>

#include <vector>
#include <array>

template<typename T>
void output1(const T &obj) {
for(auto i: obj)
std::cout << i << ", ";
std::cout << "\b\b \n";
}

template<typename T>
void output2(const T &obj) {
for(auto p = obj.begin(); p != obj.end(); ++p)
std::cout << *p << ", ";
std::cout << "\b\b \n";
}

void test_array() {
    using namespace std;
    array<int, 5> x1; 
    cout << "x1.size() = " << x1.size() << endl; 
    x1.fill(42); 
    x1.at(0) = 999; 
    x1[4] = -999; 
    cout << "x1: ";
    output1(x1);
    cout << "x1: ";
    output2(x1);

    array<int, 5> x2(x1);
    cout << boolalpha << (x1 == x2) << endl;
    x2.fill(22);
    cout << "x2: ";
    output1(x2);
    swap(x1, x2);
    cout << "x1: ";
    output1(x1);
    cout << "x2: ";
    output1(x2);
}

void test_vector() {
    using namespace std;
    vector<int> v1;
    cout << v1.size() << endl; 
    cout << v1.max_size() << endl; 
    v1.push_back(55); 
    cout << "v1: ";
    output1(v1);
    vector<int> v2 {1, 0, 5, 2};
    v2.pop_back();
    v2.erase(v2.begin()); 
    v2.insert(v2.begin(), 999); 
    v2.insert(v2.end(), -999); 
    cout << v2.size() << endl;
    cout << "v2: ";
    output2(v2);
    vector<int> v3(5, 42); 
    cout << "v3: ";
    output1(v3);
    vector<int> v4(v3.begin(), v3.end()-2); 
    cout << "v4: ";
    output1(v4);
}

void test_string() {
    using namespace std; 
    string s1{"oop"};
    cout << s1.size() << endl;
    for(auto &i: s1)
    i -= 32;
    s1 += "2023";
    s1.append(", hello");
    cout << s1 << endl;
}
int main() {
    using namespace std;
    cout << "===========测试1: array模板类基础用法===========" << endl;
    test_array();
    cout << "\n=========测试2：vector模板类基础用法==========" << endl;
    test_vector();
    cout << "/n=========测试3：string类基础用法==============" << endl;
    test_string();
}

 

#include <iostream>
#include <complex>

void test_std_complex() {
    using namespace std;
    complex<double> c1{3,4}, c2{4,5};
    const complex<double> c3{c2};
    
    cout << "c1 = " << c1 << endl;
    cout << "c2 = " << c2 << endl;
    cout << "c3 = " << c3 << endl;
    cout << "c3.real = " << abs(c1) << endl;
    
    cout << boolalpha;
    cout << "c1 == c2:" << (c1 == c2) << endl;
    cout << "c3 == c2:" << (c3 == c2) << endl;
    
    complex<double> c4 = 2;
    cout << "c4 = " << c2 << endl;
    c4 += c1;
    cout << "c4 = " << c4 << endl;
}

int main() {
    test_std_complex();
}

 

#include <iostream>
#include <string>

using namespace std;

class T {
public:
    T(int x = 0, int y = 0);
    T(const T &t);
    T(T &&t);
    ~T();
    
    void set_m1(int x);
    int get_m1() const;
    int get_m2() const;
    void display() const;
    
    friend void func();
    
private:
    int m1,m2;
    
public:
    static void disply_count();
    
public:
    static const string doc;
    static const int max_count;
    
private:
    static int count;
};


const string T::doc{"a simple class"};
const int T::max_count = 99;
int T::count = 0;

T::T(int x, int y):m1{x}, m2{y} {
    ++count;
    cout << "constructor called.\n";
}

T::T(const T &t):m1{t.m1}, m2{t.m2} {
    ++count;
    cout << "copy constructor called.\n";
}

T::T(T &&t):m1{t.m1}, m2{t.m2} {
    ++count;
    cout << "move constructor called.\n";
}

T::~T() {
    --count;
    cout << "destructor called.\n";
}

void T::set_m1(int x) {
    m1 = x;
}

int T::get_m1() const {
    return m1;
}

int T::get_m2() const {
    return m2;
}

void T::display() const {
    cout << m1 << "," << m2 << endl;
}


void T::disply_count(){
    cout << "T objects:" << count << endl; 
}

void func() {
    T t1;
    t1.set_m1(55);
    t1.m2 = 77;
    t1.display();
}

void test(){
    cout << "T class info: " << T::doc << endl;
    cout << "T objects max_count: " << T::max_count << endl;
    T::disply_count() ;
    
    T t1;
    t1.display();
    t1.set_m1(42);
    
    T t2{t1};
    t2.display();
    
    T t3{std::move(t1)};
    t3.display();
    t1.display();
    T::disply_count();
}

int main(){
    cout << "==========测试类==========" << endl;
    test();
    cout << endl;
    
    cout << "==========测试友元函数func()=========="  << endl;
    func();
}

 

#include <iostream> 
#include <string>
#include <iomanip>

using namespace std;

class Rect
{
public:
    Rect();
    Rect(int l, int w);
    Rect(const Rect &r);
    
    double len()const{return lenth;}
    double wide()const{return width;}
    double area()const{return lenth*width;}
    double circumference()const{return (lenth+width)*2;}
    void resize(double times);
    void resize(double l_times, double w_times);
    
    static string doc;
    static int size_info(){return count;}
    ~Rect() {count--;}
    
private:
    double lenth, width;
    static int count;
};

Rect::Rect(){
    lenth = 2.0;
    width = 1.0;
    count++;
}

Rect::Rect(int l, int w){
    lenth = l;
    width = w;
    count++;
}

Rect::Rect(const Rect &r){
    lenth = r.lenth;
    width = r.width;
    count++;
}


void Rect::resize(double times){
    lenth *= times;
    width *= times;
}

void Rect::resize(double l_times, double w_times){
    lenth *=l_times;
    width *=w_times;
}

int Rect::count = 0;
string Rect::doc = "a simple Rect class";

void output (const Rect &r) {
    cout << "矩形信息:" << endl;
    cout << fixed << setprecision(2);
    cout << "长：   " << left << r.len() << endl;
    cout << "宽：   " << left << r.wide() << endl;
    cout << "面积： " << left << r.area() << endl;
    cout << "周长： " << left << r.circumference() << endl;
}


void test () {
    cout << "矩形类信息：" << Rect::doc << endl;
    cout << "当前矩形对象数目：" << Rect::size_info() << endl;
    Rect r1;
    output(r1);
    
    Rect r2(4,3);
    output(r2);
    
    Rect r3(r2);
    r3.resize(2);
    output(r3);
    r3.resize(5,2);
    output(r3);
    cout << "当前矩形对象数目：" << Rect::size_info() << endl; 
}

int main(){
    test();
    cout <<"当前矩形对象数目：" << Rect::size_info() <<endl;
}

 

#include <iostream> 
#include <cmath>


using namespace std;


class Complex{
public:
    Complex();
    Complex(double real0);
    Complex(double real0,double imag0);
    Complex(const Complex &x);
    
    double get_real()const {return real;}
    double get_imag()const {return imag;}
    void show()const;
    void add(const Complex &x);
    
    friend Complex add(Complex x1, Complex x2);
    friend bool is_equal(const Complex &x1,const Complex &x2);
    friend double abs(const Complex &x);
    
private:
    double real,imag;
};

Complex::Complex(){
    real = 0;
    imag = 0;
}

Complex::Complex(double real0){
    real = real0;
    imag = 0;
}

Complex::Complex(double real0,double imag0) {
    real = real0;
    imag = imag0;
}

Complex::Complex(const Complex &x){
    real = x.real;
    imag = x.imag;
}


void Complex::show() const {
    
    using namespace std;
    if(real == 0 && imag == 0) {cout << 0;} 
    else if(real == 0){cout << imag << "i"; } 
    else if(imag == 0){cout << real;}
    else {
        if (imag > 0){
            cout << real << " + " << imag << "i" ;
    }
        else if(imag < 0) {
            cout << real << " - " << -imag << "i" ;
}
}
}

void Complex::add(const Complex &x){
    real = real+x.real;
    imag = imag+x.imag;
} 

Complex add(Complex x1, Complex x2) {
    double real,imag;
    x1.real = x1.real + x2.real;
    x2.imag = x1.imag + x2.imag;
    return x1;
}

bool is_equal(const Complex &x1, const Complex &x2) {
    bool real,imag;
    real = x1.real == x2.real;
    imag = x1.imag == x2.imag;
    return real && imag;
}
double abs(const Complex &x) {
    return sqrt(pow(x.real, 2) + pow(x.imag, 2));
}

void test(){
    using namespace std;
    
    Complex c1(3,-4);
    const Complex c2(4.5);
    Complex c3(c1);
    
    cout << "c1 = ";
    c1.show();
    cout << endl;
    
    cout << "c2 = ";
    c2.show();
    cout << endl;
    cout << "c2.imag = " << c2.get_imag() << endl;
    
    cout << "c3 = ";
    c3.show();
    cout << endl;
    
    cout << "abs(c1) = ";
    cout << abs(c1) <<endl;
    
    cout << boolalpha;
    cout << "c1 == c3 : " << is_equal(c1,c3) << endl;    
    cout << "c1 == c2 : " << is_equal(c1,c2) << endl;    
    
    Complex c4;
    c4 = add(c1,c2);
    cout << "c4 = c1 + c2 = ";
    c4.show();
    cout << endl;
    
    c1.add(c2);
    cout << "c1 += c2," << "c1 = ";
    c1.show();
    cout << endl;
}

int main() {
    test();
}