有两个矩阵a和b,均为2行3列。求两个矩阵之和，重载运算符“+”，使之能用于矩阵相加。如c=a+b。，重载插入运算符”<<”和流提取运算符“>>”,使之能用于该矩阵的输入和输出。

好的，这是一个关于C++中矩阵运算符重载的问题。下面是一份可能的代码实现：

#include <iostream>

class Matrix {
private:
    int row, col;
    int **data;

public:
    Matrix(int row, int col) {
        this->row = row;
        this->col = col;
        data = new int*[row];
        for (int i = 0; i < row; i++) {
            data[i] = new int[col];
        }
    }

    Matrix(const Matrix& other) {
        row = other.row;
        col = other.col;
        data = new int*[row];
        for (int i = 0; i < row; i++) {
            data[i] = new int[col];
            for (int j = 0; j < col; j++) {
                data[i][j] = other.data[i][j];
            }
        }
    }

    ~Matrix() {
        for (int i = 0; i < row; i++) {
            delete[] data[i];
        }
        delete[] data;
    }

    Matrix operator+(const Matrix& other) const {
        if (row != other.row || col != other.col) {
            throw std::invalid_argument("Matrix dimensions do not match.");
        }
        Matrix result(row, col);
        for (int i = 0; i < row; i++) {
            for (int j = 0; j < col; j++) {
                result.data[i][j] = data[i][j] + other.data[i][j];
            }
        }
        return result;
    }

    friend std::ostream& operator<<(std::ostream& os, const Matrix& matrix) {
        for (int i = 0; i < matrix.row; i++) {
            for (int j = 0; j < matrix.col; j++) {
                os << matrix.data[i][j] << " ";
            }
            os << std::endl;
        }
        return os;
    }

    friend std::istream& operator>>(std::istream& is, Matrix& matrix) {
        for (int i = 0; i < matrix.row; i++) {
            for (int j = 0; j < matrix.col; j++) {
                is >> matrix.data[i][j];
            }
        }
        return is;
    }
};

int main() {
    Matrix a(2, 3);
    Matrix b(2, 3);
    std::cout << "Enter matrix a:" << std::endl;
    std::cin >> a;
    std::cout << "Enter matrix b:" << std::endl;
    std::cin >> b;
    Matrix c = a + b;
    std::cout << "a + b = " << std::endl << c;
    return 0;
}

这份代码定义了一个`Matrix`类，其中包含矩阵的行数、列数和矩阵数据。重载了运算符`+`使之能够进行矩阵加法，重载了运算符`<<`和`>>`使之能够进行输入和输出。在`main`函数中，我们首先定义了两个矩阵`a`和`b`，分别输入它们的值，然后进行加法运算，输出结果。