实验三

task 4:

hpp:

#ifndef VECTOR_INT_HPP
#define VECTOR_INT_HPP

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

cpp:

#include <iostream>
#include"vector_int.hpp"
using namespace std;
int main() {
    int n;
    cout << "输入数组长度： "<<endl;
    cin >> n;
    Vector_int x0(n);
    x0.print();
    int n1, x;
    cout << "数组长度和初始值： "<<endl;
    cin >> n1 >> x;
    Vector_int x1(n1, x);
    cout << "x1=";
    x1.print();
    Vector_int x2(x1);
    cout << "x2=";
    x2.print();
    x2.at(0) = 126;
    cout << "x2=";
    x2.print();
}

 

 

task 5:

hpp:

 

#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
};


// 类Matrix的实现：待补足
// ×××
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 (auto i = 0; i < lines * cols; i++)
        p[i] = X.p[i];
}
Matrix::~Matrix() {
    delete []p;
}
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) {
    assert(i*j >= 0 && i*j< cols*lines);
    return p[i * cols + j ];
}
double Matrix::at(int i, int j) const {
    assert(i*j >= 0 && i*j< cols*lines);
    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

 

cpp:

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

int main()
{
    using namespace std;

    double x[] = { 10, 200, 30, 40, 500, 600 };

    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, 300);
    m3.print();
}