C++矩阵求和（重载运算符）

【问题描述】有两个矩阵a和b,均为2行3列。求两个矩阵之和。重载流插入运算符“<<”和流提取运算符“>>”,使之能用该矩阵的输入和输出。
【输入形式】input value of matrix:11 22 33 44 55 66

                    input value of matrix:12 13 14 15 16 17
【输出形式】Matirx a:

                    11 22 33

                    44 55 66

                   Matrix b:

                   12 13 14

                   15 16 17

                  Matrix c=Matrix a+Matrix b

                  23 35 47

                  59 71 83

//矩阵求和（2） 
#include 
#include 
using namespace std;
class Array
{
public:
    Array();
    friend Array operator+(Array a1,Array a2);//破坏封装性 
    friend istream & operator >>(istream &input,Array &c1);
    friend ostream & operator <<(ostream &output,Array &c1);
private:
    int arr[2][3];
};
Array::Array()//初始化矩阵为零矩阵 
{
    int i, j;
    for (i=0; i<2; i++)
        for (j=0; j<3;j++)
            arr[i][j]=0;
}
Array operator+(Array a1, Array a2)//重载运算符+
{
    Array a3;
    int i, j;
    for (i=0; i<2; i++)
        for (j=0; j<3; j++)
            a3.arr[i][j]=a1.arr[i][j]+a2.arr[i][j];
    return a3;
}
istream & operator >>(istream &input,Array &c1)//重载运算符>>
{     
    int i,j;  
    for(i=0;i<2;i++)  
        for(j=0;j<3;j++)  
            input>>c1.arr[i][j];
	return input;
}
ostream & operator <<(ostream &output,Array &c1)//重载运算符<<
{      
    output<>a;
    cout<>b;
    cout<