编程打卡：C语言程序设计

#include <iostream>
#include <iomanip>
using namespace std;
class Matrix {
    private:
    int row;
    int column;
    int **mat = nullptr;
    public:
    Matrix(int r = 1,int c = 1):row(r),column(c) {
        mat = new int*[row];
        for (int i = 0; i < row; i++)
            mat[i] = new int[column];
    }
    Matrix(const Matrix &m):row(m.row),column(m.column) {
        mat = new int*[row];
        for (int i = 0; i < row; i++) {
            mat[i] = new int[column];
            for (int j = 0; j < column; j++)
                mat[i][j] = m.mat[i][j];
        }
    }
    ~Matrix() {
        for (int i = 0; i < row; i++)
            delete [] mat[i];
        delete [] mat;
    }
    void input() {
        for (int i = 0; i < row; i++)
            for (int j = 0; j < column; j++)
                cin >> mat[i][j];
    }
    void display() {
        for (int i = 0; i < row; i++) {
            for (int j = 0; j < column; j++)
                cout << setw(10) << mat[i][j];
            cout << endl;
        }
    }
    Matrix operator*(const Matrix &m) {
        if (column == 1 && row == 1) {
            Matrix temp(m.row,m.column)
            for (int i = 0; i < m.row; i++)
                for (int j = 0; j < m.column; j++)
                    temp.mat[i][j] = mat[0][0] * m.mat[i][j];
            return temp;
        }
        if (m.column == 1 && m.row == 1) {
            Matrix temp(row,column)
            for (int i = 0; i < row; i++)
                for (int j = 0; j < column; j++)
                    temp.mat[i][j] = mat[i][j] * m.mat[0][0];
            return temp;
        }
        Matrix temp(row,m.column);
        for (int i = 0; i < row; i++)
            for (int j = 0; j < m.column; j++) {
                temp.mat[i][j] = 0;
                for (int k = 0; k < column; k++)
                    temp.mat[i][j] += mat[i][k] * m.mat[k][j];
            }
        return temp;
    }
};
int main () {
    int r1,c1,r2,c2;
    cin >> r1 >> c1;
    Matrix m1(r1,c1);
    m1.input();
    cin >> r2 >> c2;
    Matrix m2(r2,c2);
    m2.input();
    if (c1 == r2 || (c1 == 0 && r2 == 0)) {
        Matrix m3 = m1 * m2;
        m3.display();
    }
    cout << "Invalid Matrix multiplication!" << endl;
    return 0;
    return 0;
}