> 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 > <mailto: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 algogeeks@googlegroups.com > <mailto:algogeeks@googlegroups.com>. > To unsubscribe from this group, send email to > algogeeks+unsubscr...@googlegroups.com > <mailto: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. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
