实验4 类与数组、指针

实验任务5

vectorInt.hpp

#pragma once

#include <iostream>
using namespace std;

class vectorInt {
private:
    int length;
    int *array;

public:
    vectorInt(int n);
    vectorInt(int n, int value);
    vectorInt(const vectorInt& X);
    ~vectorInt();

    int & at(int i) const ; 
    int get_size() const ;

    friend void output(const vectorInt &Y);
};

vectorInt::vectorInt(int n) : length(n)
{
    array = new int[length];
    cout << "constructor 1 called." << endl;
}

vectorInt::vectorInt(int n, int value) : length(n)
{
    array = new int[length];
    for (int i = 0; i < length; i++)
         array[i] = value;
    cout << "constructor 2 called." << endl;
}

vectorInt::vectorInt(const vectorInt &X) : length(X.length)
{
    length = X.length;
    array = new int[length];
    for (int i = 0; i < length; i++)
         array[i] = X.array[i];
    
    cout << "copy constructor called." << endl;
}

vectorInt::~vectorInt()
{
    free(array);

    cout << "destructor called." << endl;
}

int & vectorInt::at(int i) const
{
    return array[i];
}

int vectorInt::get_size() const
{
    return length;
}

void output(const vectorInt &Y)
{
    for (int i = 0; i < Y.length; i++)
         cout << Y.array[i] << ", " ;
    cout << "\b " << endl;
}

task5.cpp

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

void test()
{
    using namespace std;

    int n;
    cin >> n;

    vectorInt x1(n);
    for(auto i = 0; i < n; i++)
        x1.at(i) = i * i;

    output(x1);

    vectorInt x2(n, 42);
    vectorInt x3(x2);

    output(x2);
    output(x3);

    x2.at(0) = 77;

    output(x2);
    output(x3);
}

int main()
{
    test();
}

测试截图：

 

实验任务6 

Matrix.hpp

#pragma once

#include <iostream>

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

class Matrix {
public:
    Matrix(int n);
    Matrix(int n, int m);
    Matrix(const Matrix &X);
    ~Matrix();

    void set(const double *pvalue);
    void set(int i, int j, int value);
    double &at(int i, int j);
    double at(int i, int j) const;
    int get_lines() const { return lines; }
    int get_cols() const { return cols; }
    void print() const;

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

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 (int i = 0; i < lines * cols; i++)
    {
        p[i] = X.p[i];
    }
}

Matrix::~Matrix() {}

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[cols * i + j] = value;
}

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

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

void Matrix::print() const
{
    for (int i = 0; i < lines; i++)
    {
        for (int j = 0; j < cols; j++)
        {
            cout << at(i, j) << ", ";
        }
        cout << endl;
    }
}

task6.cpp

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

void test()
{
    using namespace std;

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

    Matrix m1(3, 2);
    //Matrix m1(4, 5);
    m1.set(x);
    m1.print();
    cout << "the first line is: " << endl;
    cout << m1.at(0, 0) << " " << m1.at(0, 1) << endl;
    cout << endl;

    Matrix m2(2, 3);
    //Matrix m2(5, 4);
    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();
}

int main()
{
    test();
}

测试截图1：

测试截图2：