首页 > 其他分享 >类与数组、指针

类与数组、指针

时间:2023-11-05 23:13:31浏览次数:34  
标签:const cout Point int void vectorPoint 数组 指针

任务1

point.hpp

#pragma once

#include <iostream>
using std::cout;
using std::endl;

class Point {
public:
Point(int x0 = 0, int y0 = 0);
~Point() = default;

int get_x() const;
int get_y() const;
void show() const;
void move(int new_x, int new_y);

private:
int x, y;
};

Point::Point(int x0, int y0): x{x0}, y{y0} {
}

int Point::get_x() const {
return x;
}

int Point::get_y() const {
return y;
}

void Point::show() const {
cout << "(" << x << ", " << y << ")" << endl;
}

void Point::move(int new_x, int new_y) {
x = new_x;
y = new_y;
}

task.cpp

#include <iostream>
#include "point.hpp"
#include <vector>

using std::vector;
using std::cin;

// 输出vector<Point>对象内所有点的坐标
void output(const vector<Point> &v) {
for(auto &t: v)
t.show();
}

void test() {
int n;
cout << "输入动态Point数组类对象中元素个数: ";
cin >> n;

vector<Point> x(n);
cout << "x对象中所有点坐标信息: " << endl;
output(x);

vector<Point> y(x); // 基于vector<Point>对象x构建对象y
cout << "\nx对象中所有点坐标信息: " << endl;
output(y);

cout << "\n更新x对象......" << endl;
x.at(0).move(30, 50); // 更新对象x内索引为0的点对象坐标
x.push_back(Point(2, 2)); // 向x对象末尾添加一个点对象

cout << "\nx对象中所有点坐标信息: " << endl;
output(x);
cout << "\ny对象中所有点坐标信息: " << endl;
output(y);
}

int main() {
test();
}

运行结果:

 不发生变化;

深复制。

任务2

point.hpp

#pragma once

#include <iostream>
using std::cout;
using std::endl;

class Point {
public:
Point(int x0 = 0, int y0 = 0);
~Point() = default;

int get_x() const;
int get_y() const;
void show() const;
void move(int new_x, int new_y);

private:
int x, y;
};

Point::Point(int x0, int y0): x{x0}, y{y0} {
}

int Point::get_x() const {
return x;
}

int Point::get_y() const {
return y;
}

void Point::show() const {
cout << "(" << x << ", " << y << ")" << endl;
}

void Point::move(int new_x, int new_y) {
x = new_x;
y = new_y;
}

vectorPoint.hpp

#pragma once

#include "point.hpp"
#include <cassert>
#include <iostream>

class vectorPoint{
public:
vectorPoint(int n);
~vectorPoint();

int get_size() const; // 获得当前动态数组内元素个数
Point& at(int index); // 返回下标为index的元素引用
Point& at(int index) const; // 返回下标为index的元素const引用

private:
int size; // 动态数组的大小
Point *ptr;
};

vectorPoint::vectorPoint(int n) : size{n} {
ptr = new Point[n];
}

vectorPoint::~vectorPoint() {
delete[] ptr;
}

int vectorPoint::get_size() const {
return size;
}

Point& vectorPoint::at(int index) {
assert(index >= 0 && index < size); // 宏,在测试模式下工作。如果不满足条件,则程序终止
return ptr[index];
}

Point& vectorPoint::at(int index) const {
assert(index >= 0 && index < size);
return ptr[index];
}

task.cpp

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

// 输出vectorPoint对象内的所有数据
void output(const vectorPoint &v) {
    for(auto i = 0; i < v.get_size(); ++i)
        v.at(i).show();
}

// 测试vectorPoint类:构造对象、复制构造对象
void test() {
    using namespace std;

    int n;
    cout << "输入vectorPoint对象中元素个数: ";
    cin >> n;

    vectorPoint x(n);
    cout << "x对象中所有点坐标信息: " << endl;
    output(x);

    vectorPoint y(x);
    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);

    cout << "\n更新x对象中点坐标信息......" << endl;
    x.at(0).move(30, 50);
    x.at(1).move(-1, -1);

    cout << "x对象中所有点坐标信息: " << endl;
    output(x);

    cout << "\ny对象中所有点坐标信息: " << endl;
    output(y);
}

int main() {
    test();
}
实验结果

发生变化;

浅复制;

浅复制。

任务3

point.hpp

#pragma once

#include <iostream>
using std::cout;
using std::endl;

class Point {
public:
Point(int x0 = 0, int y0 = 0);
~Point() = default;

int get_x() const;
int get_y() const;
void show() const;
void move(int new_x, int new_y);

private:
int x, y;
};

Point::Point(int x0, int y0): x{x0}, y{y0} {
}

int Point::get_x() const {
return x;
}

int Point::get_y() const {
return y;
}

void Point::show() const {
cout << "(" << x << ", " << y << ")" << endl;
}

void Point::move(int new_x, int new_y) {
x = new_x;
y = new_y;
}

vectorpoint.hpp

#pragma once

#include "point.hpp"
#include <cassert>
#include <iostream>

class vectorPoint{
public:
vectorPoint(int n);
vectorPoint(const vectorPoint &vp);
~vectorPoint();

int get_size() const; // 获得当前动态数组内元素个数
Point& at(int index); // 返回下标为index的元素引用
Point& at(int index) const; // 返回下标为index的元素const引用

private:
int size; // 动态数组的大小
Point *ptr;
};

vectorPoint::vectorPoint(int n) : size{n} {
ptr = new Point[n];
}

vectorPoint::vectorPoint(const vectorPoint &vp): size{vp.size}, ptr{new Point[size]} {
for(auto i = 0; i < size; ++i)
ptr[i] = vp.ptr[i];
}

vectorPoint::~vectorPoint() {
delete[] ptr;
}

int vectorPoint::get_size() const {
return size;
}

Point& vectorPoint::at(int index) {
assert(index >= 0 && index < size); // 宏,在测试模式下工作。如果不满足条件,则程序终止
return ptr[index];
}

Point& vectorPoint::at(int index) const {
assert(index >= 0 && index < size);
return ptr[index];
}

task.cpp

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

// 输出vectorPoint对象内的所有数据
void output(const vectorPoint &v) {
for(auto i = 0; i < v.get_size(); ++i)
v.at(i).show();
}

// 测试vectorPoint类:构造对象、复制构造对象
void test() {
using namespace std;

int n;
cout << "输入vectorPoint对象中元素个数: ";
cin >> n;

vectorPoint x(n);
cout << "x对象中所有点坐标信息: " << endl;
output(x);

vectorPoint y(x);
cout << "\ny对象中所有点坐标信息: " << endl;
output(y);

cout << "\n更新x对象中点坐标信息......" << endl;
x.at(0).move(30, 50);
x.at(1).move(-1, -1);

cout << "x对象中所有点坐标信息: " << endl;
output(x);

cout << "\ny对象中所有点坐标信息: " << endl;
output(y);
}

int main() {
test()

}

实验结果

不发生变化;

深复制;

当类的成员中包含指针域成员时,默认复制构造函数进行浅复制。浅复制仅复制指针,新指针与原指针指向同一内存区域;深复制复制数据并为之分配单独的内存区域,新指针指向新的内存区域。

任务4

task1.cpp

#include <iostream>
using namespace std;

// 函数声明
void swap1(int &rx, int &ry); // 引用作为形参
void swap2(int *px, int *py); // 指针作为形参
void print(int x, int y); // 普通变量作为形参

// 测试代码
void test() {
int x = 3, y = 4;

print(x, y);
swap1(x, y); // 函数调用,注意:引用作为形参时,实参形式
print(x, y);

cout << endl;

x = 3, y = 4;
print(x, y);
swap2(&x, &y); // 函数调用,注意:指针作为形参时,实参形式
print(x, y);
}

int main() {
test();
}

// 函数定义:交换两个变量(引用变量作为形参)
void swap1(int &rx, int &ry) {
int t;

t = rx; rx = ry; ry = t;
}

// 函数定义:交换两个变量(指针变量作为形参)
void swap2(int *px, int *py) {
int t;

t = *px; *px = *py; *py = t;
}

// 函数定义:输出两个变量(普通变量作为形参)
void print(int x, int y) {
std::cout << "x = " << x << ", y = " << y << ";

}

实验结果

 

task2.cpp

#include <iostream>
#include <typeinfo>
using namespace std;

int main() {
int a;

int &ra = a;
ra = 4;

int *pa = &a;
*pa = 5;

// 以十六进制形式输出普通变量a, 引用变量ra,指针变量pa的地址
cout << "&a = " << hex << &a << endl;
cout << "&ra = " << hex << &ra << endl;
cout << "&pa = " << hex << &pa << "\n\n";

// 输出普通变量a, 引用变量ra,指针变量pa的值
cout << "a = " << a << endl;
cout << "ra = " << a << endl;
cout << "pa = " << hex << pa << endl;

// 输出指针变量pa指向的变量的值
cout << "*pa = " << *pa << "\n\n";

// 输出普通变量a,引用变量ra, 指针变量pa的类型信息
cout << "type a: " << typeid(a).name() << endl;
cout << "type ra: " << typeid(ra).name() << endl;
cout << "type pa: " << typeid(pa).name() << endl;
}

实验结果

task3.cpp

#include <iostream>
#include <vector>

using namespace std;

template<typename T>
void output(const T &x) {
for(auto i: x)
std::cout << i << ", ";
std::cout << "\b\b \n";
}

template<typename T>
void square1(T &x) {
for(auto i: x) // i是普通类型
i *= i;
}

template<typename T>
void square2(T &x) {
for(auto &i: x) // i是引用类型
i *= i;
}

void test1() {
vector<int> x {1, 2, 3, 4, 5};

cout << "动态int型数组对象x内的元素值: ";
output(x);

cout << "调用函数square1()......" << endl;
square1(x);

cout << "动态int型数组对象x内的元素值: ";
output(x);
}

void test2() {
vector<int> x {1, 2, 3, 4, 5};

cout << "动态int型数组对象x内的元素值: ";
output(x);

cout << "调用函数square2()......" << endl;
square2(x);

cout << "动态int型数组对象x内的元素值: ";
output(x);
}

int main() {
cout << "测试1: " << endl;
test1();

cout << "\n测试2: " << endl;
test2();
}

实验结果

指针类型:本质是地址,可以独立存在,用于存放数据的地址。可以对指针本身进行操作,也可以通过指针去间接操作数据。引用类型:本质是别名,不能独立存在,依赖于源数据。所有操作同步反馈到源数据上。

任务5

.hpp

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

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

void output(const vectorInt &vi) {
for(auto i = 0; i < vi.get_size(); ++i)
cout << vi.at(i) << ", ";
cout << "\b\b \n";
}

void test() {
int n;
cout << "输入vectorInt对象中元素个数: ";
cin >> n;

vectorInt x1(n); // 构造动态int数组对象x1,包含n个元素,不对元素初始化
for(auto i = 0; i < n; ++i)
x1.at(i) = i*i;
cout << "vectorInt对象x1: ";
output(x1);

vectorInt x2(n, 42); // 构造动态int数组对象x1,包含n个元素,每个元素初始值为42
cout << "vectorInt对象x2: ";
output(x2);
vectorInt x3(x2); // 使用x2构造x3
cout << "vectorInt对象x3: ";
output(x3);

cout << "更新vectorInt对象x2......\n";
x2.at(0) = 77;
x2.at(1) = -999;

cout << "vectorInt对象x2: ";
output(x2);
cout << "vectorInt对象x3: ";
output(x3);
}

int main() {
test();
}

.cpp

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

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

void output(const vectorInt &vi) {
for(auto i = 0; i < vi.get_size(); ++i)
cout << vi.at(i) << ", ";
cout << "\b\b \n";
}

void test() {
int n;
cout << "输入vectorInt对象中元素个数: ";
cin >> n;

vectorInt x1(n); // 构造动态int数组对象x1,包含n个元素,不对元素初始化
for(auto i = 0; i < n; ++i)
x1.at(i) = i*i;
cout << "vectorInt对象x1: ";
output(x1);

vectorInt x2(n, 42); // 构造动态int数组对象x1,包含n个元素,每个元素初始值为42
cout << "vectorInt对象x2: ";
output(x2);
vectorInt x3(x2); // 使用x2构造x3
cout << "vectorInt对象x3: ";
output(x3);

cout << "更新vectorInt对象x2......\n";
x2.at(0) = 77;
x2.at(1) = -999;

cout << "vectorInt对象x2: ";
output(x2);
cout << "vectorInt对象x3: ";
output(x3);
}

int main() {
test();
}

实验结果

任务6

.hpp

#pragma once

#include <iostream>
#include <cassert>

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

// 类Matrix的声明
class Matrix {
public:
Matrix(int n, int m); // 构造函数,构造一个n*m的矩阵
Matrix(int n); // 构造函数,构造一个n*n的矩阵
Matrix(const Matrix &x); // 复制构造函数, 使用已有的矩阵X构造
~Matrix();

void set(const double *pvalue); // 用pvalue指向的连续内存块数据按行为矩阵赋值
void set(int i, int j, double value); // 设置矩阵对象索引(i,j)的元素值为value

double& at(int i, int j) const; // 返回矩阵对象索引(i,j)的元素引用
double& at(int i, int j); // 返回矩阵对象索引(i,j)的元素引用

int get_lines() const; // 返回矩阵对象行数
int get_cols() const; // 返回矩阵对象列数

void print() const; // 按行打印输出矩阵对象元素值

private:
int lines; // 矩阵对象内元素行数
int cols; // 矩阵对象内元素列数
double *ptr;
};

// 类Matrix的实现
Matrix::Matrix(int n, int m) : lines{n}, cols{m} {
ptr = new double[n * m];
}
Matrix::Matrix(int n) : lines{n}, cols{n} {
ptr = new double[n * n];
}
Matrix::Matrix(const Matrix &x) : lines{x.lines}, cols{x.cols} {
ptr = new double[x.lines * x.cols];
for (int i = 0; i < lines * cols; i++)
ptr[i] = x.ptr[i];
}
Matrix::~Matrix() {
delete[] ptr;
}

void Matrix::set(const double *pvalue) {
for (int i = 0, j = 0; i < lines * cols; i++, j++)
ptr[i] = pvalue[j];
}
void Matrix::set(int i, int j, double value) {
ptr[i * lines + j] = value;
}

double& Matrix::at(int i, int j) const {
return ptr[i * lines + j];
}
double& Matrix::at(int i, int j) {
return ptr[i * lines + j];
}

int Matrix::get_lines() const {
return lines;
}
int Matrix::get_cols() const {
return cols;
}

void Matrix::print() const {
int s = 0;
for (int i = 0; i < lines; i++) {
cout << ptr[s];
s++;
for (int j = 1; j < cols; j++, s++)
cout << ", " << ptr[s];
cout << '\n';
}
}

.cpp

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

using namespace std;

const int N1 = 3;
const int N2 = 2;

// 输出一个矩阵对象中索引为index对应的行的所有元素值
void output(const Matrix &m, int index) {
for(auto j = 0; j < m.get_cols(); ++j)
cout << m.at(index, j) << ", ";
cout << "\b\b \n";
}

void test() {


double x[N1*N2] = {3, 1, 4, 1, 5, 9};

Matrix m1(N1, N2); // 创建一个N1×N2矩阵
m1.set(x); // 用一维数组x的值按行为矩阵m1赋值
cout << "矩阵对象m1: " << endl;
m1.print(); // 打印矩阵m1的值
cout << "矩阵对象m1第0行是: " << endl;
output(m1, 0);
cout << endl;

Matrix m2(N2, N1);
m2.set(x);
cout << "矩阵对象m2: " << endl;
m2.print();
cout << "矩阵对象m2第0行是: " << endl;
output(m2, 0);
cout << endl;

Matrix m3(m2); // 用矩阵m2构造新的矩阵m3
m3.set(0, 0, 999); // 讲矩阵对象m2索引(0,0)元素设为999
cout << "矩阵对象m3:" << endl;
m3.print();
cout << endl;

Matrix m4(2); // 创建一个2*2矩阵对象
m4.set(x); // 用一维数组x的值按行为矩阵m4赋值
cout << "矩阵对象m4:" << endl;
m4.print();
}

int main() {
test();
}

实验结果

实验总结:

通过这次实验,我知道了什么是深复制、浅复制,能根据问题场景合理编码(复制构造函数)实现深复制

了解了重载成员函数、返回引用类型等用法

 



标签:const,cout,Point,int,void,vectorPoint,数组,指针
From: https://www.cnblogs.com/lwjddd/p/17811483.html

相关文章

  • 实验三 类与数组、指针
     1.实验任务1point.hpp1#include<iostream>2#include"point.hpp"3#include<vector>4usingstd::vector;5usingstd::cin;6//输出vector<Point>对象内所有点的坐标7voidoutput(constvector<Point>&v){8for(aut......
  • 实验三 类与数组指针
    第一个任务#pragmaonce#include<iostream>usingstd::cout;usingstd::endl;classPoint{public:Point(intx0=0,inty0=0);~Point()=default;intget_x()const;intget_y()const;voidshow()const;voidmove(intnew......
  • 实验3 类与数组、指针
    1、实验任务1源码Point.hpp#pragmaonce#include<iostream>usingstd::cout;usingstd::endl;classPoint{public:Point(intx0=0,inty0=0);~Point()=default;intget_x()const;intget_y()const;voidshow()const;void......
  • 用线段树来接树状数组类的问题
    大致解决的问题就是区间查询以及单点的修改#include<bits/stdc++.h>#defineintlonglongusingnamespacestd;constintN=5e5+10;inta[N],tag[N<<2];struct{ struct{ intl,r,sum; }tr[N<<2]; voidpush_up(inti){ tr[i].sum=tr[i<<1].sum+tr[i<......
  • 实验三 类与数组,指针
    任务1:1.代码:point.hpp:1#pragmaonce23#include<iostream>4usingstd::cout;5usingstd::endl;6classPoint{7public:8Point(intx0=0,inty0=0);9~Point()=default;10intget_x()const;11intget_y()const;12voidshow(......
  • js把json字符串转成json数组
    如何将JSON字符串转换为JSON数组。假设你有以下JSON字符串,它表示一个简单的数组,其中包含两个对象:'[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}]'要将这个JSON字符串转换为JavaScript中的数组对象,你可以使用JSON.parse()方法。这个方法接受一个J......
  • 查找数组中元素
    1.代码#include<stdio.h>intmain(){inta[6]={60,75,95,80,65,90},b;scanf("%d",&b);if(b!=a[0]&&b!=a[1]&&b!=a[2]&&b!=a[3]&&b!=a[4]&&b!=a[5]){printf("NotIncluded......
  • 实验3 类与数组指针
    task1 point.hpp#pragmaonce#include<iostream>usingstd::cout;usingstd::endl;classPoint{public:Point(intx0=0,inty0=0);~Point()=default;intget_x()const;intget_y()const;void......
  • 实验三 类与数组、指针
    任务一point.hpp#pragmaonce#include<iostream>usingstd::cout;usingstd::endl;classPoint{public:Point(intx0=0,inty0=0);~Point()=default;intget_x()const;intget_y()const;voidshow()const;voidmove(intnew_x,intnew_y);pri......
  • 2023年11月第一周题解-------数组
    1.问题A:LY学长的随机数解题思路第一种思路是先去重后排序第二种思路是先排序再去重解题方法暴力遍历#define_CRT_SECURE_NO_WARNINGS#include<stdio.h>#include<stdlib.h>#include<string.h>#include<math.h>#include<time.h>#defineN10voidquickSort......