类的封装

#ifndef ARRAY_H
#define ARRAY_Hclass DoubArray
{
private:int m_length;double* m_pointer;public:DoubArray(int len);DoubArray(const DoubArray& obj);int length();bool get(int index, double& value);bool set(int index, double value);void sort(const DoubArray& obj);void show(const DoubArray& obj);~DoubArray();
};#endif // ARRAY_H

类的实现

#include "Array.h"
#include <iostream>
using namespace std;//构造函数，用于创建数组并初始化
DoubArray::DoubArray(int len)
{m_pointer = new double[len];for(int i = 0; i < len; i++){m_pointer[i] = 0;}m_length = len;
}//拷贝构造函数，用于深拷贝
DoubArray::DoubArray(const DoubArray& obj)
{m_length = obj.m_length;m_pointer = new double[obj.m_length];for(int i = 0; i < obj.m_length; i++){m_pointer[i] = obj.m_pointer[i];}
}//数组排序
void DoubArray::sort(const DoubArray& obj)
{int len = obj.m_length;for(int i = 0; i < len; i++){for(int j = 0; j < len - i; j++){if( obj.m_pointer[j] < obj.m_pointer[j+1] ){double temp = obj.m_pointer[j];obj.m_pointer[j] = obj.m_pointer[j+1];obj.m_pointer[j+1] = temp;}}}
}//获取数组长度
int DoubArray::length()
{return m_length;
}//获取数组成员
bool DoubArray::get(int index, double& value)
{bool ret = (0 <= index) && (index < length());if( ret ){value = m_pointer[index];}return ret;
}//设置数组成员
bool DoubArray::set(int index, double value)
{bool ret = (0 <= index) && (index < length());if( ret ){m_pointer[index] = value;}return ret;
}//遍历数组
void DoubArray::show(const DoubArray& obj)
{int len = obj.m_length;for(int i = 0; i  < len ; i++){cout << obj.m_pointer[i] << endl;}
}//析构函数，销毁数组
DoubArray::~DoubArray()
{delete[]m_pointer;
}

主函数调用

#include <iostream>
#include "Array.h"
using namespace std;int main()
{double score = 0;int num = 0;cout << "请输入学生人数：";cin >> num;DoubArray stu_a(num);for(int i = 0; i < num; i++){cout << "请输入第" << i+1 << "个学生的成绩：";cin >> score;stu_a.set(i, score);}cout << "学生成绩降序排列如下：";stu_a.sort(stu_a);stu_a.show(stu_a);return 0;
}

程序效果