实验三

task5

#ifndef MATRIX_H
#define MATRIX_H
#include <iostream>
#include <cassert>
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[lines * cols];
    for (int i = 0; i < lines * cols; i++)
        p[i] = 0;
}
Matrix::Matrix(int n, int m)
{
    lines = n;
    cols = m;
    p = new double[lines * cols];
    for (int i = 0; i < lines * cols; i++)
        p[i] = 0;
}
Matrix::Matrix(const Matrix& X)
{
    lines = X.lines;
    cols = X.cols;
    p = new double[lines * cols];
    double* mid = X.p;
    for (int i = 0; i < lines * cols; i++)
        p[i] = *(mid++);
}
void Matrix::set(const double* pvalue)
{
    for (int i = 0; i < lines * cols; i++)
        p[i] = *(pvalue++);
}
void Matrix::set(int i, int j, int value)
{
    p[cols * i + j] = value;
}
double& Matrix::at(int n, int m)
{
    return p[cols * n + m];
}
double Matrix::at(int n, int m) const
{
    return p[cols * n + m];
}
int Matrix::get_lines() const
{
    return lines;
}
int Matrix::get_cols() const
{
    return cols;
}
void Matrix::print() const
{
    int i, j;
    for (i = 0; i < lines; i++)
    {
        for (j = 0; j < cols; j++)
        {
            std::cout << p[i * cols + j] << "  ";
        }
        std::cout << std::endl;
    }
}
Matrix::~Matrix()
{
    delete[] p;
}
// 类Matrix的实现：待补足
// ×××


#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();
}

 

 

task4

 

#ifndef vector_int_HPP
#define vector_int_HPP
#include<iostream>
using namespace std;

class vector_int {
private: int size; int value; int* p;
public: vector_int(int n);
        vector_int(int n, int m);
        vector_int(const vector_int& x);
        int at(int n);
        ~vector_int() { cout << "Destructor called." << endl; }
};
vector_int::vector_int(int n)
{
    size = n;
    p = new int[size];
    cout << "Constructot called." << endl;
}
vector_int::vector_int(int n, int m)
{
    size = n;
    value = m;
    p = new int[size];
    for (int i = 0; i < size; i++)
        *p = value;
    cout << "Constructot called." << endl;
}
vector_int::vector_int(const vector_int& x)
{
    size = x.size;
    value = x.value;
    p = x.p;
    cout << "Constructot called." << endl;
}
int vector_int::at(int n)
{
    return *(p + n);
}

#endif 

#include"vector_int.hpp"
#include<iostream>
using namespace std;
int main()
{
    int n;
    cin >> n;
    vector_int z(n);
    vector_int x(n, 6);
    vector_int y(x);
    cout << y.at(0) << endl;
}