实验3 类与数组、指针

#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();
}

#ifndef VECTORINT_HPP
#define VECTORINT_HPP
#include <iostream>

class vectorInt {
private:
    int* data; // 动态数组指针
    int size; // 数组大小
public:
    // 构造函数，动态指定数组大小
    vectorInt(int n) : size(n) {
        std::cout << "constructor vectorInt(int n) called." << std::endl;
        data = new int[size];
    }
    // 构造函数，动态指定数组大小，并将每个元素初始化为特定值value
    vectorInt(int n, int value) : size(n) {
        std::cout << "constructor vectorInt(int n, int value) called." << std::endl;
        data = new int[size];
        for (int i = 0; i < size; ++i) {
            data[i] = value;
        }
    }
    // 拷贝构造函数，实现深复制
    vectorInt(const vectorInt& other) : size(other.size){
        std::cout << "copy constructor called." << std::endl;
        if (other.data != nullptr){
            data = new int[size];
            for (int i = 0; i < size; ++i){
                data[i] = other.data[i];
            }
        } else{
            data=nullptr;
       }

   }

   ~vectorlnt(){
      delete[]data;

      cout<<"destructor called"<<std::end1;
   }


// 获取数组中数据项个数

int get_size() const{

returnsize;

}

// 访问第i个数据项

int at(ing index)const{

if(index>=0&&index<size){

return data[index];

}else{

std::cout<<"Invalid index!"<<std::end1;

return 0;

}

}


};

endif

#include "vectorInt.hpp"
#include <iostream>

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

void output(const vectorInt &vi) {
    for (int i = 0; i < vi.get_size(); ++i) {
        cout << vi.at(i) << " ";
    }
    cout << endl;
}


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();
}

#pragma once
#include <iostream>
#include <cassert>

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

class Matrix {
public:
    Matrix(int n, int m);
    Matrix(int n);
    Matrix(const Matrix &x);
    ~Matrix();
    void set(const double *pvalue); // 矩阵赋值
    void setcint i, int j, double value); // 设置矩阵对象索引（i，j）的元素值为value
    double& atcint 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 getlines() const; // 返回矩阵对象行数
    int getcols() const; // 返回矩阵对象列数
    void printO) const;  |/按行打印输出矩阵对象元素值

private:
    int lines;
    int cols;
    double *ptr;
};


#include "matrix.hpp"


Matrix::Matrix(int n, int m): lines(n), cols(m), ptr(new double[n*m]) {}

Matrix::Matrix(int n): lines(n), cols(n), ptr(new double[n*n]) {}

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

void Matrix::set(const double pvalue) {
    for (auto i = 0; i < linescols;++i)
        ptr[i] = pvalue[i];
}

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

double& Matrix::atcint 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::printO) const {
    for(auto i = 0;i<lines;++i){
        for(auto j=0;j<cols;++j)
            cout << at(i,j)<<",";
        cout << "\b\b \n";
    }
}

#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();
}