定义一个数组类Array，实现二维数组的旋转.

定义一个数组类Array，实现二维数组的旋转。通过重载正号运算符“ + ”，顺时针旋转 90°，即使元素
b[1]li]变成b[i[M - 1 - i]; 通过重载负号运算符“ - ”，逆时针旋转90°，即使元素b[i][i]变成b[M - 1 - j][i]。具体要求如下:
(1)私有数据成员:
int b[M][M]; //数据成员，存放数组 
(2)公有成员函数:
Array(int(*p)[M]) : 构造函数，以形参初始化数据成员; void operator +() : 重载函数，使数组顺时针旋转90°;
friend void operator-(Array& b) : 重载函数，使数组逆时针旋转90°; void print() :输出数据成员。
(3)对所定义的类进行测试。要求输出原始数组和旋转之后的数组。

#include<iostream>
#define M 4
using namespace std;
class Array
{
private:
	int arr[M][M];
public:
	Array(int(* p)[M])
	{
		for (int i = 0; i < M; i++)
		{
			for (int j = 0; j < M; j++)
			{
				arr[i][j] = p[i][j];
			}
		}
	}
	/*
	 1  2  3  4    13  9    5  1                                 4  8  12   16
	 5  6  7  8    14  10   6  2                                 3  7  11   15
	 9 10 11 12    15  11   7  3                                 2  6  10   14
	13 14 15 16    16  12   8  4  b[i][j]=a[j][m-1-i]            1  5   9   13  b[i][j]=a[m-1-j][i]
	*/
	Array operator-()
	{
		int arr2[M][M];
		for (int i = 0; i < M; i++)
		{
			for (int j = 0; j < M; j++)
			{
				arr2[M - 1 - j][i]=arr[i][j];
			}
		}
		for (int i = 0; i < M; i++)
		{
			for (int j = 0; j < M; j++)
			{
				arr[i][j] = arr2[i][j];
			}
		}
		return *this;
	}
	friend Array operator+(Array& a);
	void show()
	{
		for (int i = 0; i < M; i++)
		{
			for (int j = 0; j < M; j++)
			{
				cout << arr[i][j] << "\t";
			}
			cout << endl;
		}
	}
};
Array operator+(Array &a)
{
	int arr2[M][M];
	for (int i = 0; i < M; i++)
	{
		for (int j = 0; j < M; j++)
		{
			arr2[j][M - 1 - i] = a.arr[i][j];
			a.arr[i][j] = arr2[i][j];
		}
	}
	for (int i = 0; i < M; i++)
	{
		for (int j = 0; j < M; j++)
		{
			a.arr[i][j] = arr2[i][j];
		}
	}
	return a;
}
int main() {
	int a1[M][M] = { 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16 };
	Array arr(a1);
	arr.show();
	cout << endl;
	arr.operator-().show();
	cout << endl;
	int a2[M][M] = { 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16 };
	Array arr2(a2);
	operator+(arr2).show();
	cout << '\n';
}