实验三 类和对象Ⅱ

任务四：

//vector_int.hpp

#ifndef BALL_H
#define BALL_H

#include<iostream>
#include<cstdlib>

using namespace std;

class Vector_int{
private:
    int n, m;
    int * p;
public:
    Vector_int(int n0);
    Vector_int(int n0, int m0);
    Vector_int(Vector_int & x);
    ~Vector_int(); 
    int & at(int i);
    void print(){
        for(int i=0; i<n; i++)
            cout << p[i] << " ";
        cout << endl;
    }
}; 

Vector_int::Vector_int(int n0){
    p = new int [n0];
    n = n0;
    for(int i=0; i<n0; i++)
        p[i] = 0;
    cout << "构造函数1被调用"  << endl;    
}
Vector_int::Vector_int(int n0, int m0){
    p = new int [n0];
    n = n0;
    for(int i=0; i<n0; i++)
        p[i] = m0;
    cout << "构造函数2被调用"  << endl;
}
Vector_int::Vector_int(Vector_int & x){
    n = x.n;
    p = new int [n];
    for(int i=0; i<n; i++)
        p[i] = x.p[i];
    cout << "复制构造函数被调用"  << endl;
}
Vector_int::~Vector_int(){
    delete[] p;
    cout << "析构函数被调用" << endl; 
}
int & Vector_int::at(int i){
    return p[i];
}

#endif

//task4.cpp

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

using namespace std;

int main(){
    int n;
    cin >> n;
    Vector_int x(n);
    x.print();
    Vector_int y(n, 6);
    y.print();
    Vector_int z(x);
    z.at(0) = 999; 
    z.print();
}

运行结果截图：

任务五：

//Matrix.hpp

#ifndef MATRIX_H
#define MATRIX_H 

#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;
    int get_cols() const;
    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 [X.lines*X.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[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];
}
int Matrix::get_lines() const{
    return lines;
}
int Matrix::get_cols() const{
    return cols;
}
void Matrix::print() const{
    for(int i=0; i<cols*lines; i++){
        cout << p[i] << ", ";
        if(!((i+1)%cols))
            cout << " 
";
    }
}
#endif

//task5.cpp

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

int main(){
    using namespace std;
    
    double x[] = {1, 2, 3, 4, 5, 6};
    
    Matrix m1(3, 2);
    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);
    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();
}

运行结果截图：