The intuitive proof maybe that if you try to expand the recursion over a few steps such that it tends to go towards T(1) then you never see a term greater(in order) than O(n^2) ..
On Wed, Apr 1, 2009 at 2:56 PM, Miroslav Balaz <[email protected]>wrote: > but you need some kind of proof, for that.i alsow see from first sight that > it is O(n^2), but i wane just fo verify that. > > 2009/4/1 Ajinkya Kale <[email protected]> > >> I dont think you even need to solve the recursion .. >> by looking at it it seems to be O(n^2) right ? >> >> >> On Wed, Apr 1, 2009 at 2:18 PM, Miroslav Balaz >> <[email protected]>wrote: >> >>> no that is just asymptotic recursion. >>> the answer is between n^2 and n^2log n >>> >>> of coure the answer is n^2; >>> >>> T(n)=n^2/2-n^2/4+n^2=n^2/4+n^2=T(n/2)+n^2=by master theorem n^2 >>> >>> T(n)< B(n)=2B(n/2)+n^2 what is by master theorem n^2 log n >>> >>> n >>> n/2 n/2 >>> n/4 n/4 n/4 n/4 >>> >>> T(n/2)=2T(n/4)-4T(n/8)+n^2/4 >>> >>> T(n)=4T(n/4)-8T(n/8)+n^2/2-4T(n/4)+n^2=-8T(n/8)+3n^2/2 >>> >>> you may pick up what is solution >>> >>> 2009/3/31 Arunachalam <[email protected]> >>> >>> What is the base value of this recursion? Without a base value the >>>> recursion is not solvable? >>>> >>>> There should be some base value like T(x) = 1 where x <= 1. >>>> >>>> regards, >>>> Arun. >>>> >>>> On Mon, Mar 30, 2009 at 12:35 AM, nikoo <[email protected]>wrote: >>>> >>>>> >>>>> Hello everybody >>>>> >>>>> I need the solution to the following recursion equation >>>>> >>>>> T(n) = 2 T (n/2) - 4 T (n/4) + n^2 >>>>> >>>>> does anybody know how to solve this equation? >>>>> I appreciate any help >>>>> >>>>> thanks >>>>> nikoo >>>>> >>>>> >>>> >>>> >>>> -- >>>> =================================== >>>> want to know more about me >>>> http"//ww.livejournal.com/users/arunachalam >>>> >>>> >>>> >>>> >>> >>> >>> >> >> >> -- >> Ciao, >> Ajinkya >> >> >> >> > > > > -- Ciao, Ajinkya --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/algogeeks -~----------~----~----~----~------~----~------~--~---
