i want to find make a program for insertion in AVL binary tree therefore i want to find balance factor of a node by subtracting depth of right child from dephth of left child
how will i find this depth.
i am using array representetion of the tree.

Have you looked at Wikipedia?

You really haven't given us much information to work with. "An array representation" can mean many, many different things.

Post us the code you have so far and we'll help you fix it.

Hope this helps.