@Dheeraj: This is a great solution. My first thought has complexity O(n^3) and uses O(1) extra space. For your algorithm, sorting an array of size n^2 would be O(n^2 log n), so your algorithm has complexity O(n^2 log n) and uses extra space of size O(n^2). We can see the tradeoff of space for complexity.
Dave On Aug 27, 1:11 pm, Dheeraj Sharma <dheerajsharma1...@gmail.com> wrote: > create an array of all possible PAIR sums..that would be done in > O(n^2)..sort it..O(log(n))now..search this array for two pairs..that sum to > the required value.. > this can be done by maintaining two index..one at the lowest value..one at > the highest value..and moving them accordingly..(if sum of pair exceeds > given value..move up highest value pointer..else move down..lowest value > pointer) > > On Sat, Aug 27, 2011 at 10:59 PM, tech coder <techcoderonw...@gmail.com>wrote: > > > Given an array A[] and a integer num. Find four no.s in the array whose sum > > is equal to given num. > > > -- > > You received this message because you are subscribed to the Google Groups > > "Algorithm Geeks" group. > > To post to this group, send email to algogeeks@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. > > -- > *Dheeraj Sharma* > Comp Engg. > NIT Kurukshetra > +91 8950264227 -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algogeeks@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.
