trouble with pointers

[Crakrjack]

Hi,
Ive got a struct called Node that contains, among other things, a pointer to a vector of pgm objects. (pgm is a class i've created)

struct Node
{
	int label;
	vector <pgm> *ptr;
	Node* lessNode;
	Node* moreNode;
};

in another class, i create a vector and a Node and am having trouble assigning the pointer in the Node to point to my new vector.

vector <pgm> lessData;	
       Node* left;
	left->ptr=&lessData;

This all compiles ok, but the last line in the code above causes a segmentation fault. Any clues as to what i'm doing wrong here?
Cheers.

I should mention Node is declared on its own in Node.h and has no idea what pgm is. including pgm.h in node.h makes no change to the problem.

[Bourgond Aries]

You haven't created a new node yet.
Node *left = new Node;

[Crakrjack]

Thanks mate, I need to do more coding, I should have picked that up.