recursion tree and binary tree cost calculation

Posted by Tony on Stack Overflow See other posts from Stack Overflow or by Tony
Published on 2010-05-04T19:31:32Z Indexed on 2010/05/04 19:38 UTC
Read the original article Hit count: 279

Filed under:
|

Hi all,

I've got the following recursion:

T(n) = T(n/3) + T(2n/3) + O(n)

The height of the tree would be log3/2 of 2. Now the recursion tree for this recurrence is not a complete binary tree. It has missing nodes lower down. This makes sense to me, however I don't understand how the following small omega notation relates to the cost of all leaves in the tree.

"... the total cost of all leaves would then be Theta (n^log3/2 of 2) which, since log3/2 of 2 is a constant strictly greater then 1, is small omega(n lg n)."

Can someone please help me understand how the Theta(n^log3/2 of 2) becomes small omega(n lg n)?

© Stack Overflow or respective owner

Related posts about algorithm

Related posts about computer-science