C++实验内容： 假设square_matrix是n阶整型方阵，请实现下列运算： （1）cin>> square_matrix （2）cout<< square_matrix （3）IntMatrix(n)生成一个n阶单位矩阵 （4）square_matrix+IntMatrix(n) （5）square_matrix_A=square_matrix_B

下面是 C++ 实现：

#include <iostream>
using namespace std;

class IntMatrix {
private:
    int **matrix; // 二维动态数组
    int n; // 方阵阶数

public:
    // 构造函数，创建一个 n 阶方阵，默认为零矩阵
    IntMatrix(int n) {
        this->n = n;
        matrix = new int*[n];
        for (int i = 0; i < n; i++) {
            matrix[i] = new int[n];
            for (int j = 0; j < n; j++) {
                matrix[i][j] = 0;
            }
        }
    }

    // 拷贝构造函数
    IntMatrix(const IntMatrix& other) {
        n = other.n;
        matrix = new int*[n];
        for (int i = 0; i < n; i++) {
            matrix[i] = new int[n];
            for (int j = 0; j < n; j++) {
                matrix[i][j] = other.matrix[i][j];
            }
        }
    }

    // 重载输入运算符
    friend istream& operator>>(istream& in, IntMatrix& m) {
        for (int i = 0; i < m.n; i++) {
            for (int j = 0; j < m.n; j++) {
                in >> m.matrix[i][j];
            }
        }
        return in;
    }

    // 重载输出运算符
    friend ostream& operator<<(ostream& out, const IntMatrix& m) {
        for (int i = 0; i < m.n; i++) {
            for (int j = 0; j < m.n; j++) {
                out << m.matrix[i][j] << " ";
            }
            out << endl;
        }
        return out;
    }

    // 重载加法运算符
    IntMatrix operator+(const IntMatrix& other) const {
        IntMatrix m(n);
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                m.matrix[i][j] = matrix[i][j] + other.matrix[i][j];
            }
        }
        return m;
    }

    // 重载赋值运算符
    IntMatrix& operator=(const IntMatrix& other) {
        if (this != &other) {
            // 先删除原有的矩阵
            for (int i = 0; i < n; i++) {
                delete[] matrix[i];
            }
            delete[] matrix;

            // 重新分配内存
            n = other.n;
            matrix = new int*[n];
            for (int i = 0; i < n; i++) {
                matrix[i] = new int[n];
                for (int j = 0; j < n; j++) {
                    matrix[i][j] = other.matrix[i][j];
                }
            }
        }
        return *this;
    }

    // 析构函数，释放动态内存
    ~IntMatrix() {
        for (int i = 0; i < n; i++) {
            delete[] matrix[i];
        }
        delete[] matrix;
    }
};

int main() {
    int n;
    cin >> n;

    // 输入方阵
    IntMatrix square_matrix(n);
    cin >> square_matrix;

    // 输出方阵
    cout << square_matrix;

    // 生成单位矩阵
    IntMatrix unit_matrix(n);
    for (int i = 0; i < n; i++) {
        unit_matrix.matrix[i][i] = 1;
    }

    // 方阵加单位矩阵
    IntMatrix result = square_matrix + unit_matrix;
    cout << result;

    // 赋值
    IntMatrix square_matrix_A = square_matrix;
    cout << square_matrix_A;

    return 0;
}