Thanks everyone; that O(n^2) is an awesome solution. Regards, Akash Agrawal http://tech-queries.blogspot.com/
On Thu, Dec 2, 2010 at 12:21 PM, fenghuang <fenghaungyuyi...@gmail.com>wrote: > @anoop > when you find some i and j(i < j) meet the condition i.e. asq[i] + asq[j] > == asq[k], you can merge the same value without rollback. > in this sense, you are right. > > On Thu, Dec 2, 2010 at 2:26 PM, anoop chaurasiya < > anoopchaurasi...@gmail.com> wrote: > >> @fenghuang try this array: >> a[]={3,3,3,3,3,3,4,4,4,4,4,4,5} >> so asq[]={9,9,9,9,9,9,16,16,16,16,16,16,25} >> here as u can see the total number of requisite triple pairs are 6*6=36, >> in general for above array total number of pairs is (n/2)*(n/2) i.e. n^2/4 >> where n is the size of the array. >> by using O(n) algo and since you are choosing them one by one,u can't >> include all of them as they are of order O(n^2). >> so removing repetitions is the only option i think.. >> >> On Wed, Dec 1, 2010 at 11:37 PM, fenghuang <fenghaungyuyi...@gmail.com>wrote: >> >>> @anoop >>> in fact, it always work even if there are repeated elements, because they >>> don't change the decision. >>> in detail, assume ii, ,jj, kk is one of the answers, then >>> a[ii]+a[jj]=a[kk]. since the array is sorted, so a[ii-1]+a[jj] <= a[kk] and >>> a[ii] + a[jj+1] >= a[kk]. >>> so when you try the pair of 'ii-1' and 'jj', the next step must be >>> calculate a[ii] + a[jj] as long as a[ii-1]+a[jj] is not equal to a[kk]. the >>> same to the pair 'ii' and 'jj+1'. >>> the algorithm is correct and in the whole procedure, repeated elements >>> don't affect the decision. >>> I'm sorry for my poor English. >>> Thank You! >>> >>> On Thu, Dec 2, 2010 at 12:14 PM, anoop chaurasiya < >>> anoopchaurasi...@gmail.com> wrote: >>> >>>> sorry for the interruption,we can make it work even if the elements are >>>> repeated, by removing the duplicacy in linear time(as the array is already >>>> sorted) and taking a count of no. of duplicates in the seperate array. >>>> >>>> On Wed, Dec 1, 2010 at 9:37 PM, Senthilnathan Maadasamy < >>>> senthilnathan.maadas...@gmail.com> wrote: >>>> >>>>> A small correction to the algorithm above. In Step 3, instead of >>>>> finding *any* pair (a,b) such that a+b = x we need to find *all* such >>>>> pairs. However the complexity remains the same. >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "Algorithm Geeks" group. >>>>> To post to this group, send email to algoge...@googlegroups.com. >>>>> To unsubscribe from this group, send email to >>>>> algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> >>>>> . >>>>> For more options, visit this group at >>>>> http://groups.google.com/group/algogeeks?hl=en. >>>>> >>>> >>>> >>>> >>>> -- >>>> Anoop Chaurasiya >>>> CSE (2008-2012) >>>> NIT DGP >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Algorithm Geeks" group. >>>> To post to this group, send email to algoge...@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> >>>> . >>>> For more options, visit this group at >>>> http://groups.google.com/group/algogeeks?hl=en. >>>> >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Algorithm Geeks" group. >>> To post to this group, send email to algoge...@googlegroups.com. >>> To unsubscribe from this group, send email to >>> algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> >>> . >>> For more options, visit this group at >>> http://groups.google.com/group/algogeeks?hl=en. >>> >> >> >> >> -- >> Anoop Chaurasiya >> CSE (2008-2012) >> NIT DGP >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Algorithm Geeks" group. >> To post to this group, send email to algoge...@googlegroups.com. >> To unsubscribe from this group, send email to >> algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> >> . >> For more options, visit this group at >> http://groups.google.com/group/algogeeks?hl=en. >> > > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to algoge...@googlegroups.com. > To unsubscribe from this group, send email to > algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algoge...@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.