Reference: Introduction to Algorithm 2nd Edition. Section 4.3 Master Theorem.
The very question has been explained. Its mentioned that:
"The master method does not apply to the recurrence
T(n) = 2T(n/2) + n lg n,
even though it has the proper form: a = 2, b = 2, f(n) = n lg n, and . It might seem that case 3 should apply, since f(n) = n lg n is asymptotically larger than . The problem is that it is not polynomially larger. Consequently, the recurrence falls into the gap between case 2 and case 3 of master theorem."

The recurrence relation is n*(log ²n)

Possibly, you didn't click on 'Register for Manthan' on the right pane of the event page http://codefest.org.in/event.php?name=manthan . Check out the "how to participate?" section of the event page.

Exactly! Wonderful collaboration :)

Yay! CodeFest rocks :)

http://mirror.codeforces.com/blog/entry/1473#comments

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