Matrix(const Matrix &other) {
        rows = other.rows;
        columns = other.columns;
        data = new T * [rows];
        for (size_t i = 0; i < rows; ++i) {
            for (size_t j = 0; j < columns; ++j) {
                data[i][j] = other.data[i][j];
            }
        }
    }

    Matrix& operator= (const Matrix& other) {
        rows = other.rows;
        columns = other.columns;
        data = new T * [rows];
        for (size_t i = 0; i < rows; ++i) {
            for (size_t j = 0; j < columns; ++j) {
                data[i][j] = other.data[i][j];
            }
        }
    }