实验3 类和对象Ⅱ

#ifndef VECTOR_INT_H
#define VECTOR_INT_H
# include <iostream>
# include <cassert>
using namespace std;
class Vector_int {
public:
    Vector_int(int n, int value):size(n)
    {
        p = new int[size];
        for (int i = 0;i < size;i++)
            p[i] = value;
        cout << "constructor called." << endl;
    }
    Vector_int(int n) :size(n)
    {
        p = new int[size]();
        cout << "constructor called." << endl;
    }
    Vector_int(const Vector_int& x)
    {
        size = x.size;
        p = new int[size];
        for (int i = 0;i < size;i++)
            p[i] = x.p[i];
    }
    ~Vector_int()
    {
        delete[]p;
        cout << "deleting..." << endl;
    }
    int& at(int index)
    {
        assert(index >= 0 && index < size);
        return p[index];
    }
    void show()const
    {
        for (auto i = 0;i < size;++i)
            cout << p[i] << " ";
            cout << endl;
    }
private:
    int size;
    int* p;
};
#endif

# include "vector_int.hpp"
# include <iostream>
using namespace std;
int main()
{
    int n;
cin >> n;
Vector_int x1(n);
x1.show();
Vector_int x2(n, 6);
x2.show();
Vector_int y(x2);
y.show();
y.at(0) = 999;
y.show();
return 0;
}

 

#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
};


// 类Matrix的实现：待补足
// ×××
using namespace std;
Matrix::Matrix(int n):lines(n),cols(n)
{
    p = new double[lines * cols];
}
Matrix::Matrix(int n, int m):lines(n),cols(m)
{
    p = new double[lines * cols];
}
Matrix::Matrix(const Matrix& X)
{
    lines = X.lines;
    cols = X.cols;
    p = new double[lines * cols];
    for (int i = 0;i < lines * cols;i++)
        p[i] = X.p[i];
}
Matrix::~Matrix()
{
    delete[]p;
}
void Matrix::set(const double* pvalue)
{
    for (int i = 0;i < lines * cols;i++)
        p[i] = pvalue[i];
}
void Matrix::set(int i, int j, int value)
{
    p[(i + 1) * (j + 1) - 1] = value;
}
double& Matrix::at(int i, int j)
{
    return p[(i + 1) * (j + 1) - 1];
}
double Matrix::at(int i, int j)const
{
    return p[(i + 1) * (j + 1) - 1];
}
int Matrix::get_lines()const
{
    return lines;
}
int Matrix::get_cols()const
{
    return cols;
}
void Matrix::print()const
{
    int k = 0;
    for (int i = 0;i < lines;i++)
    {
        for (int j = 0;j < cols;j++)
            cout << p[k++] << " ";
        cout << endl;
    }
}
#endif

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

int main()
{
    using namespace std;

    double x[] = {2, 5, 6, 7, 8, 6};

    Matrix m1(2, 3);    
    m1.set(x);          
    m1.print();        
    cout << "the first line is: " << endl;
    cout << m1.at(0, 0) << " " << m1.at(0, 1) <<m1.at(0,2) << " " <<endl;
    cout << endl;

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

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