Creating binary tree from an array

I have to create a binary tree from an array of elements level wise..i.e a[0] is root.a[1] and a[2] are a[0]'s children.a[4],a[5] are a[2] children and so on.

Can someone tell me how to do this recursively or non-recursively?

Thanks

what programming language? and did you search google first?

It's in C++ and i searched a lot in Google. It's NOT the binary search tree that we have to implement in which the root value is taken and elements smaller than the root are placed at the left and larger elements are placed on the right.

It's actually a threaded binary tree that we have to implement. Here we are not concerned about the actual values of the elements.All we have to do is take an array of values as user input and create a binary tree as I told above.
array[0] -- root
array[1] -- root's left child
array[2] -- root's right child
array[3] -- array[1] 's left child
array[4] -- array[1]'s right child
and so on...

the tree would look like this
-----------------a[0]-------------

----------a[1]----------a[2]------

-------a[3]----a[4]---a[5]---a[6]---

----a[7]--a[8] .......................

and so on.(hope the above looks like a tree,I tried my best to show it!!)
So, it's basically filling up the tree level wise from the elements in the given array(irrespective of the actual values of the elements)

To Madhyena,

Thanks for the link, but the way i have to create my binary tree -- that's no where mentioned in the link you sent me. I am very willing to learn myself given the right resource.Let me know if you find something related to my description which I posted earlier.

Thanks!!

the first google link should answer your question.

The link which I followed -- It shows how to count the nodes. I am not sure how my problem is cleared.

I just did a program in Java that dealt with trees, but not in arrays, but apparently the way I did it was 'unorthodox', and I worked with a friend... we weren't allowed to work together, so we both got 0's. We were lucky she didn't give us an F though for cheating. Because I'm too busy to figure out exactly what part might help you, here's my whole program. It's java, but it might help you with an idea, probably not. To have it work with arrays you just need a way of keeping track of what array position your in and then have each new node advance that spot.