QVector<QVector<Node*> > strange behaviour

Veaceslav

Hello, i've searched the forum, but i didn't find anything relevant to my problem:

I have a class named Node that contains QVector<QVector<Node*> > link;

and with this constructor:

@ Node(int conMax)
{
link = QVector<QVector<Node*> >(conMax);

}@

and i use:

@
Node* nod = new Node(4);

nod->link[2].append(anotherNode);
@

well it sometimes work but sometimes, when i made a bigger test,
it crashes and gdb reports segfault in QVector<Node*>::append(Node&*)

only after changing constructor to:
@ Node(int conMax)
{
link = QVector<QVector<Node*> >(conMax +4);

}@

crash dissapeared. I'm afraid that for even bigger input, crash can appear again.

I do something wrong?

I need the first QVector to have a certain size, so i can could insert everywhere in that range.

koahnig

conMax does only define the size of "outer" vector. How do you define the size of the "inner" vector?

Veaceslav

Well i need to define a size only for outer vector, because i use [] operator.

For inner vector i don't have a defined size, and i use append.

Or something like
@
QVector vector;

vector.append(element);
@

works without a size specified...

For inner vector i let him expand on it's own...

Wilk

Hello.
I've tried to reproduce your problem, but everything went right.
My suggetions are:

Analize you code and think of what may go wrong. This might save your time.