A better version exists where amortized order is (1) for both opreations Best, Prakhar Jain http://web.iiit.ac.in/~prakharjain/
On Mon, Mar 22, 2010 at 6:56 PM, Brian <brianfo...@gmail.com> wrote: > > How is it possible to implement a queue using a stack only? > > Interesting, but tricky... You need two stacks as Prakhar stated... > In general, if you have Stack A and Stack B, you should keep all the items > in stack A and then use stack B for processing. > > For example to insert an item: > 1. Pop all the items from A and then push them into B (this should push > the items into Stack B in reverse order) > 2. Insert the new item into A > 3. Pop all the items in B and push them back into A (again this will push > them back into Stack B in reverse order) > > Running time should be O(1)+O(2n), which is O(n) for larger values of n - > which is not good... > > To retrieve an item, pop the first item in stack A > > Hope this helps - > Regards > B > > > > On 3/22/2010 4:55 AM, Prakhar Jain wrote: > > By a do u mean a single stack ? > Otherwise if you use 2 its v simple > > Best, > Prakhar Jain > http://web.iiit.ac.in/~prakharjain/<http://web.iiit.ac.in/%7Eprakharjain/> > > > On Mon, Mar 22, 2010 at 12:56 AM, Pushpesh Gupta <pushpes...@gmail.com>wrote: > >> How is it possible to implement a queue using a stack only? >> >> -- >> 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. > > > -- > 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.
