实验三 类与对象Ⅱ

实验任务4：

#ifndef Vector_int_hpp
#define Vector_int_hpp
#include<iostream>
#include<cassert>

using namespace std;
class Vector_int{
    public:
        Vector_int(int n0);
        Vector_int(int n0, int value0);
        Vector_int(Vector_int &p);
        ~Vector_int();
        int &at(int index);
        
        void in()
        {   
            int x;
            cout<<"输入数组元素: ";
            for(auto i=0;i<n;i++)
            {
                cin>> x;
                p[i]=x;
            }
        }
        void out()
        {
            cout<<"数组元素为: ";
            for(auto i=0;i<n;i++)
            cout<<p[i]<<" ";
            cout<<endl;
        }
        void changeout()
        {
            cout<<"更改后的数组元素为: ";
            for(auto i=0;i<n;i++)
            cout<<p[i]<<" ";
            cout<<endl;
        }
    private:
        int n;
        int *p;
        
};

Vector_int::Vector_int(int n0):n(n0)
{
    cout<<"constructor1 called."<<endl;
    p=new int[n];
    for(auto i=0;i<n;i++)
    p[i]=0;
}

Vector_int::Vector_int(int n0, int value0):n(n0)
{
    cout<<"constructor2 called."<<endl;
    p=new int[n];
    for(auto i=0;i<n;i++)
    p[i]=value0;
}

Vector_int::~Vector_int()
{
    cout<<"Destructor called."<<endl;
    delete[] p;
}

Vector_int::Vector_int(Vector_int &c):n{c.n}
{
    cout<<"copy constructor called."<<endl;
    p=new int[n];
    for(auto i=0;i<n;i++)
    p[i]=c.p[i];
}

int &Vector_int::at(int index)
{
    assert(index >= 0 && index < n); 
    return p[index];
}

#endif

 

#include "Vector_int.hpp"
#include<iostream>
int main()
{
    int n,m,index;
    
    cout<<"输入数组大小: ";
    cin>>n;
    Vector_int x1(n);
    x1.out();
    x1.in();
    x1.changeout();
    x1.at(0)=999;
    cout<<"索引检查后: ";
    x1.changeout(); 
    cout<<endl;
    
    
    cout<<"输入数组大小: ";
    cin>>n;
    cout<<"输入数组元素初始值: ";
    cin>>m;
    Vector_int x2(n, 6);
    x2.out();
    x2.in();
    x2.changeout();
    x2.at(0)=999;
    cout<<"索引检查后: ";
    x2.changeout(); 
    cout<<endl;
    
    
    cout<<"调用复制构造函数"<<endl;
    Vector_int y(x1);
    y.out();
    y.at(0)=999;
    cout<<"索引检查后: ";
    y.changeout();
    
    
}

 

 实验任务5：

#ifndef MATRIX_H
#define MATRIX_H

#include <iostream>
#include <cassert>
using namespace std;
    
class Matrix
{
public:
    Matrix(int n);                     // 构造函数，构造一个n*n的矩阵
    Matrix(int n, int m);              // 构造函数，构造一个n*m的矩阵
    Matrix(const Matrix &X);           // 复制构造函数，使用已有的矩阵X构造
    ~Matrix();                         //析构函数
    void set(const double *pvalue);     // 用pvalue指向的连续内存块数据为矩阵赋值
    void set(int i, int j, int value); //设置矩阵第i行第j列元素值为value
    double &at(int i, int j);          //返回矩阵第i行第j列元素的引用
    double at(int i, int j) const;     // 返回矩阵第i行第j列元素的值
    int get_lines() const;             //返回矩阵行数
    int get_cols() const;              //返回矩列数
    void print() const;                // 按行打印输出矩阵
private:
    int lines; // 矩阵行数
    int cols;  // 矩阵列数
    double *p; // 指向存放矩阵数据的内存块的首地址
};

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

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

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

Matrix::~Matrix(){}

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

void Matrix::set(int i, int j, int value)
{
    p[i*cols+j]=value;
}

double &Matrix::at(int i, int j)
{
    return p[i*cols+j];
}

double Matrix::at(int i, int j) const
{
    return p[i*cols+j];
}

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

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

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

#endif

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

int main()
{
    using namespace std;

    double x[] = {1, 2, 3, 4, 5, 6};

    Matrix m1(3, 2);    // 创建一个3×2的矩阵
    m1.set(x);          // 用一维数组x的值按行为矩阵m1赋值
    m1.print();         // 打印矩阵m1的值
    cout << "the first line is: " << endl;
    cout << m1.at(0, 0) << " " << m1.at(0, 1) << endl;
    cout << endl;

    Matrix m2(2, 3);
    m2.set(x);
    m2.print();
    cout << "the first line is: " << endl;
    cout << m2.at(0, 0) << " " << m2.at(0, 1) << " " << m2.at(0, 2) << endl;
    cout << endl;

    Matrix m3(m2);
    m3.set(0, 0, 999);
    m3.print();
}