实验三 类与数组、指针

任务1

#pragma once 
#include <iostream>
using std::cout;
using std::endl;
class Point {
public:
    Point(int x0 = 0, int y0 = 0);
    ~Point() = default;
    int get_x() const;
    int get_y() const;
    void show() const;
    void move(int new_x, int new_y);
private:
    int x, y;
};
Point::Point(int x0, int y0) : x{ x0 }, y{ y0 } {
}
int Point::get_x() const {
    return x;
}
int Point::get_y() const {
    return y;
}
void Point::show() const {
    cout << "(" << x << ", " << y << ")" << endl;
}
void Point::move(int new_x, int new_y) {
    x = new_x;
    y = new_y;
}

#include <iostream>
#include "point.hpp"
#include <vector>
using std::vector;
using std::cin;
// 输出vector<Point>对象内所有点的坐标
void output(const vector<Point>& v) {
    for (auto& t : v)
        t.show();
}
void test() {
    int n;
    cin >> n;
    vector<Point> x(n);
    cout << "x对象中所有点坐标信息: " << endl;
    output(x);
    vector<Point> y(x); // 基于vector<Point>对象x构建对象y
    cout << "\nx对象中所有点坐标信息: " << endl;
    output(y);
    cout << "\n更新x对象: " << endl;
    x.at(0).move(30, 50); // 更新对象x内索引为0的点对象坐标
    x.push_back(Point(2, 2)); // 向x对象末尾添加一个点对象
    cout << "\nx对象中所有点坐标信息: " << endl;
    output(x);
    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);
}
int main() {
    test();
}

 

任务2

#pragma once 
#include <iostream>
using std::cout;
using std::endl;
class Point {
public:
    Point(int x0 = 0, int y0 = 0);
    ~Point() = default;
    int get_x() const;
    int get_y() const;
    void show() const;
    void move(int new_x, int new_y);
private:
    int x, y;
};
Point::Point(int x0, int y0) : x{ x0 }, y{ y0 } {
}
int Point::get_x() const {
    return x;
}
int Point::get_y() const {
    return y;
}
void Point::show() const {
    cout << "(" << x << ", " << y << ")" << endl;
}
void Point::move(int new_x, int new_y) {
    x = new_x;
    y = new_y;
}

#pragma once
#include "point.hpp"
#include <cassert>
#include <iostream>
class vectorPoint {
public:
    vectorPoint(int n);
    ~vectorPoint();
    int get_size() const; // 获得当前动态数组内元素个数
    Point& at(int index); // 返回下标为index的元素引用
    Point& at(int index) const; // 返回下标为index的元素const引用
private:
    int size; // 动态数组的大小
    Point* ptr;
};
vectorPoint::vectorPoint(int n) : size{ n } {
    ptr = new Point[n];
}
vectorPoint::~vectorPoint() {
    delete[] ptr;
}
int vectorPoint::get_size() const {
    return size;
}
Point& vectorPoint::at(int index) {
    assert(index >= 0 && index < size); // 宏，在测试模式下工作。如果不满足条件，则程序终止
        return ptr[index];
}
Point& vectorPoint::at(int index) const {
    assert(index >= 0 && index < size);
    return ptr[index];
}

#include "vectorPoint.hpp"
#include <iostream>
// 输出vectorPoint对象内的所有数据
void output(const vectorPoint& v) {
    for (auto i = 0; i < v.get_size(); ++i)
        v.at(i).show();
}
// 测试vectorPoint类：构造对象、复制构造对象
void test() {
    using namespace std;
    int n;
    cout << "输入vectorPoint对象中元素个数: ";
    cin >> n;
    vectorPoint x(n);
    cout << "x对象中所有点坐标信息: " << endl;
    output(x);
    vectorPoint y(x);
    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);
    cout << "\n更新x对象中点坐标信息......" << endl;
    x.at(0).move(30, 50);
    x.at(1).move(-1, -1);
    cout << "x对象中所有点坐标信息: " << endl;
    output(x);
    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);
}
int main() {
    test();
}

 

任务3

#pragma once
#include <iostream>
using std::cout;
using std::endl;
class Point {
public:
    Point(int x0 = 0, int y0 = 0);
    ~Point() = default;
    int get_x() const;
    int get_y() const;
    void show() const;
    void move(int new_x, int new_y);

private:
    int x, y;
};

Point::Point(int x0, int y0) : x{ x0 }, y{ y0 } {
}

int Point::get_x() const {
    return x;
}

int Point::get_y() const {
    return y;
}

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

void Point::move(int new_x, int new_y) {
    x = new_x;
    y = new_y;
}

#pragma once
#include "point.hpp"
#include <cassert>
#include <iostream>
class vectorPoint {
public:
    vectorPoint(int n);
    vectorPoint(const vectorPoint& vp);
    ~vectorPoint();
    int get_size() const; // 获得当前动态数组内元素个数
    Point& at(int index); // 返回下标为index的元素引用
    Point& at(int index) const; // 返回下标为index的元素const引用
private:
    int size; // 动态数组的大小
    Point* ptr;
};
vectorPoint::vectorPoint(int n) : size{ n } {
    ptr = new Point[n];
}
vectorPoint::vectorPoint(const vectorPoint& vp) : size{ vp.size }, ptr{ new
Point[size] } {
    for (auto i = 0; i < size; ++i)
        ptr[i] = vp.ptr[i];
}
vectorPoint::~vectorPoint() {
    delete[] ptr;
}
int vectorPoint::get_size() const {
    return size;
}
Point& vectorPoint::at(int index) {
    assert(index >= 0 && index < size); // 宏，在测试模式下工作。如果不满足条件，则程序终止
        return ptr[index];
}
Point& vectorPoint::at(int index) const {
    assert(index >= 0 && index < size);
    return ptr[index];
}

#include "vectorPoint.hpp"
#include <iostream>
// 输出vectorPoint对象内的所有数据
void output(const vectorPoint& v) {
    for (auto i = 0; i < v.get_size(); ++i)
        v.at(i).show();
}
// 测试vectorPoint类：构造对象、复制构造对象
void test() {
    using namespace std;
    int n;
    cout << "输入vectorPoint对象中元素个数: ";
    cin >> n;
    vectorPoint x(n);
    cout << "x对象中所有点坐标信息: " << endl;
    output(x);
    vectorPoint y(x);
    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);
    cout << "\n更新x对象中点坐标信息......" << endl;
    x.at(0).move(30, 50);
    x.at(1).move(-1, -1);
    cout << "x对象中所有点坐标信息: " << endl;
    output(x);
    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);
}
int main() {
    test();
}

 

任务4

#include <iostream>
using namespace std;
// 函数声明
void swap1(int& rx, int& ry); // 引用作为形参
void swap2(int* px, int* py); // 指针作为形参
void print(int x, int y); // 普通变量作为形参
// 测试代码
void test() {
    int x = 3, y = 4;
    print(x, y);
    swap1(x, y); // 函数调用，注意：引用作为形参时，实参形式
    print(x, y);
    cout << endl;
    x = 3, y = 4;
    print(x, y);
    swap2(&x, &y); // 函数调用，注意：指针作为形参时，实参形式
    print(x, y);
}
int main() {
    test();
}
// 函数定义：交换两个变量（引用变量作为形参）
void swap1(int& rx, int& ry) {
    int t;
    t = rx; rx = ry; ry = t;
}
// 函数定义：交换两个变量（指针变量作为形参）
void swap2(int* px, int* py) {
    int t;
    t = *px; *px = *py; *py = t;
}
// 函数定义：输出两个变量（普通变量作为形参）
void print(int x, int y) {
        std::cout << "x = " << x << ", y = " << y << "\n";
}

#include <iostream>
#include <typeinfo>
using namespace std;
int main() {
    int a;
    int& ra = a;
    ra = 4;
    int* pa = &a;
    *pa = 5;
    // 以十六进制形式输出普通变量a, 引用变量ra，指针变量pa的地址
    cout << "&a = " << hex << &a << endl;
    cout << "&ra = " << hex << &ra << endl;
    cout << "&pa = " << hex << &pa << "\n\n";
    // 输出普通变量a, 引用变量ra，指针变量pa的值
    cout << "a = " << a << endl;
    cout << "ra = " << a << endl;
    cout << "pa = " << hex << pa << endl;
    // 输出指针变量pa指向的变量的值
    cout << "*pa = " << *pa << "\n\n";
    // 输出普通变量a，引用变量ra, 指针变量pa的类型信息
    cout << "type a: " << typeid(a).name() << endl;
    cout << "type ra: " << typeid(ra).name() << endl;
    cout << "type pa: " << typeid(pa).name() << endl;
}

#include <iostream>
#include <vector>
using namespace std;
template<typename T>
void output(const T& x) {
    for (auto i : x)
        std::cout << i << ", ";
    std::cout << "\b\b \n";
}
template<typename T>
void square1(T& x) {
    for (auto i : x) // i是普通类型
        i *= i;
}
template<typename T>
void square2(T& x) {
    for (auto& i : x) // i是引用类型
        i *= i;
}
void test1() {
    vector<int> x{ 1, 2, 3, 4, 5 };
    cout << "动态int型数组对象x内的元素值: ";
    output(x);
    cout << "调用函数square1()......" << endl;
    square1(x);
    cout << "动态int型数组对象x内的元素值: ";
    output(x);
}
void test2() {
    vector<int> x{ 1, 2, 3, 4, 5 };
    cout << "动态int型数组对象x内的元素值: ";
    output(x);
    cout << "调用函数square2()......" << endl;
    square2(x);
    cout << "动态int型数组对象x内的元素值: ";
    output(x);
}
int main() {
    cout << "测试1: " << endl;
    test1();
    cout << "\n测试2: " << endl;
    test2();
}

 

任务5

#include<iostream>
#include<cassert>
using namespace std;
class vectorInt
{
public:
      vectorInt(int n);
      vectorInt(int n, int m);
      vectorInt(const vectorInt & vc);
      int get_size() const;
      ~vectorInt();
      int& at(int index);
      int& at(int index) const;
private:
      int size;
      int* ptr;
};
vectorInt::vectorInt(int n)
{
    size = n;
    ptr = new int[n];
    cout << "constructor vectorInt(int n) called." << endl;
}
vectorInt::vectorInt(int n, int m)
{
    size = n; ptr = new int[n];
    for (int i = 0; i < size; i++)
        ptr[i] = m;
    cout << "constructor vectorInt(int n,int value) called" << endl;
}
vectorInt::vectorInt(const vectorInt & vc)
{
    size = vc.size;
    ptr = new int[size];
    for (int i = 0; i < size; ++i)
        ptr[i] = vc.ptr[i];
    cout << "copy constructor called" << endl;
}
vectorInt::~vectorInt()
{
    delete[] ptr;
    cout << "destructor called" << endl;
}
int vectorInt::get_size() const
{
    return size;
}
int& vectorInt::at(int index)
{
    assert(index >= 0 && index < size); // 宏，在测试模式下工作。如果不满足条件，则程序终止
    return ptr[index];
}
int& vectorInt::at(int index) const
{
    assert(index >= 0 && index < size);
    return ptr[index];
}

#include "vectorInt.hpp"
#include <iostream>
using std::cout;
using std::cin;
using std::endl;
// 函数output()的定义：遍历输出vectorInt对象内的所有元素
void output(const vectorInt& vi) {
    for (int i = 0; i < vi.get_size(); ++i)
                 cout << vi.at(i) << ", ";
         cout << "\b\b \n";
}
void test() {
    int n;
    cout << "输入vectorInt对象中元素个数: ";
    cin >> n;
    vectorInt x1(n); // 构造动态int数组对象x1，包含n个元素，不对元素初始化
    for (auto i = 0; i < n; ++i)
        x1.at(i) = i * i;
    cout << "vectorInt对象x1: ";
    output(x1);
    vectorInt x2(n, 42); // 构造动态int数组对象x1，包含n个元素，每个元素初始值为42
    cout << "vectorInt对象x2: ";
    output(x2);
    vectorInt x3(x2); // 使用x2构造x3
    cout << "vectorInt对象x3: ";
    output(x3);
    cout << "更新vectorInt对象x2......\n";
    x2.at(0) = 77;
    x2.at(1) = -999;
    cout << "vectorInt对象x2: ";
    output(x2);
    cout << "vectorInt对象x3: ";
    output(x3);
}
int main() {
    test();
}

 

任务6

#pragma once
#include <iostream>
#include <cassert>
using std::cout;
using std::endl;
// 类Matrix的声明
class Matrix {
public:
    Matrix(int n, int m); // 构造函数，构造一个n*m的矩阵
    Matrix(int n); // 构造函数，构造一个n*n的矩阵
    Matrix(const Matrix& x); // 复制构造函数， 使用已有的矩阵X构造
    ~Matrix();
    void set(const double* pvalue); // 用pvalue指向的连续内存块数据按行为矩阵赋值
    void set(int i, int j, double value); // 设置矩阵对象索引(i,j)的元素值为value
    double& at(int i, int j) const; // 返回矩阵对象索引(i,j)的元素引用
    double& at(int i, int j); // 返回矩阵对象索引(i,j)的元素引用
    int get_lines() const; // 返回矩阵对象行数
    int get_cols() const; // 返回矩阵对象列数
    void print() const; // 按行打印输出矩阵对象元素值
private:
    int lines; // 矩阵对象内元素行数
    int cols; // 矩阵对象内元素列数
    double* ptr;
};
// 类Matrix的实现：待补足
// xxx
Matrix::Matrix(int n, int m) : lines{ n }, cols{ m } {
    assert(n > 0 && m > 0);
    ptr = new double[n * m];
}

Matrix::Matrix(int n) : Matrix(n, n) {}

Matrix::Matrix(const Matrix& x) : lines{ x.lines }, cols{ x.cols } {
    ptr = new double[lines * cols];
    for (int i = 0; i < lines * cols; ++i) {
        ptr[i] = x.ptr[i];
    }
}

Matrix::~Matrix() {
    delete[] ptr;
}

void Matrix::set(const double* pvalue) {
    for (int i = 0; i < lines * cols; ++i) {
        ptr[i] = pvalue[i];
    }
}

void Matrix::set(int i, int j, double value) {
    assert(i >= 0 && i < lines && j >= 0 && j < cols);
    ptr[i * cols + j] = value;
}

double& Matrix::at(int i, int j) const {
    assert(i >= 0 && i < lines && j >= 0 && j < cols);
    return ptr[i * cols + j];
}

double& Matrix::at(int i, int j) {
    assert(i >= 0 && i < lines && j >= 0 && j < cols);
    return ptr[i * cols + j];
}

int Matrix::get_lines() const {
    return lines;
}

int Matrix::get_cols() const {
    return cols;
}

void Matrix::print() const {
    for (int i = 0; i < lines; ++i) {
        for (int j = 0; j < cols; ++j) {
            cout << ptr[i * cols + j] << " ";
        }
        cout << endl;
    }
}

#include <iostream>
#include "matrix.hpp"
using namespace std;
const int N1 = 3;
const int N2 = 2;
// 输出一个矩阵对象中索引为index对应的行的所有元素值
void output(const Matrix& m, int index) {
    for (auto j = 0; j < m.get_cols(); ++j)
        cout << m.at(index, j) << ", ";
    cout << "\b\b \n";
}
void test() {
    double x[N1 * N2] = { 1, 2, 3, 4, 5, 6 };
    Matrix m1(N1, N2); // 创建一个N1×N2矩阵
    m1.set(x); // 用一维数组x的值按行为矩阵m1赋值
    cout << "矩阵对象m1: " << endl;
    m1.print(); // 打印矩阵m1的值
    cout << "矩阵对象m1第0行是: " << endl;
    output(m1, 0);
    cout << endl;
    Matrix m2(N2, N1);
    m2.set(x);
    cout << "矩阵对象m2: " << endl;
    m2.print();
    cout << "矩阵对象m2第0行是: " << endl;
    output(m2, 0);
    cout << endl;
    Matrix m3(m2); // 用矩阵m2构造新的矩阵m3
    m3.set(0, 0, 999); // 讲矩阵对象m2索引(0,0)元素设为999
    cout << "矩阵对象m3:" << endl;
    m3.print();
    cout << endl;
    Matrix m4(2); // 创建一个2*2矩阵对象
    m4.set(x); // 用一维数组x的值按行为矩阵m4赋值
    cout << "矩阵对象m4:" << endl;
    m4.print();
}
int main() {
    test();
}