invalit type 'int[int]' for array subscript

I`m trying convert QBytearray to QVector<QVector3D>.

extern "C" {
    typedef struct {
        double **vertexes;
        int top_rows_vertexes;
        int top_column_vertexes;

        double **edges;
        int top_rows_edges;
        int top_column_edges;
    }MATRIX;

    int start_processing(const char * file_name, MATRIX *date);
}

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    // сишная часть тут создаем структуру получаем имя файла и запускаем нашу сишную функцию
    MATRIX A;
    QString name = "../../test.obj";
    QByteArray str_name;
    str_name += name;
    int result = start_processing(str_name, &A);

    // тут наполняем массив 3Д координатами
    QVector<QVector3D> coords;

    for (int i = 0; i < A.top_rows_vertexes; ++i) {
        coords.append(QVector3D(A.top_rows_vertexes[0][0], A.vertexes[0][1], A.vertexes[0][2]));
    }

but I get an error. "invalid type 'int[int]' for array subscript" I need help. I ask you to explain as simple as possible because i'm just learning.

i`m tried changing type array from double to float... it didn't help

int top_rows_vertexes;

That is a plain integer

A.top_rows_vertexes[0][0]

Here you are trying to index into an integer, which obviously will not work.

You probably want to index into vertexes like for the other cases:

    coords.append(QVector3D(A.vertexes[0][0], A.vertexes[0][1], A.vertexes[0][2]));

But that is rather suspicious also. Presumably you would want to use the loop variable here, so maybe

    coords.append(QVector3D(A.vertexes[i][0], A.vertexes[i][1], A.vertexes[i][2]));