c++知识点----成员函数重载运算符

题目:

编写一个程序,用成员函数重载运算符“+”和“-”将两个二维数组相加和减,要求第一个二维数组的值由构造函数设置,另一个二维数组的值由键盘输入

用到的文件

maincpp.cpp

#define M 2
#include <iostream>
using namespace std;
#include "class.h"int main()
{cout << "请输入4个数组成一个数组:\n";double arr[2][2];for (int i = 0; i < M; i++){for (int j = 0; j < M; j++){cin >> arr[i][j];}}Array arr1;//自动设置二维数组Array arr2(arr);//传递二维数组Array arr3 = arr1 + arr2;//加Array arr4 = arr2 - arr1;//减cout << "arr3:" << endl;arr3.show();cout << "arr4:" << endl;arr4.show();system("pause");return 0;
}

class .h

#pragma once
class Array
{
public:Array();//自动设置二维数组的所有值为1Array(const double p[][M]);//用户传递一个二维数组Array operator+(Array &);//两个数组相加Array operator-(Array &);//两个数组相减void show();//显示数组
private:double a[M][M];
};
Array::Array()
{for (int i = 0; i < M; i++){for (int j = 0; j < M; j++){a[i][j] = 1;}}
}
Array::Array(const double p[][M])
{for (int i = 0; i < M; i++){for (int j = 0; j < M; j++){a[i][j] = p[i][j];}}
}
Array Array::operator+(Array &B)//采用了用成员运算符重载,可以利用this指针减少一个参数
{Array A1;for (int i = 0; i < M; i++){for (int j = 0; j < M; j++){A1.a[i][j] = a[i][j]+B.a[i][j];//a[i][j]之所以不用指定对象,是因为this指针就指向“+”号的左操作数 }}return A1;
}
Array Array::operator-(Array &B)
{Array A1;for (int i = 0; i < M; i++){for (int j = 0; j < M; j++){A1.a[i][j] =a[i][j] -B.a[i][j];}}return A1;
}
void Array::show()
{for (int i = 0; i < M; i++){for (int j = 0; j < M; j++){cout << a[i][j]<<" ";}cout << '\n';}
}

运行结果: