What do you mean by " if this number is less than elements stored in stack " There have be N comparisons in the worst case. And that way, you have to do it for every element. So it will be governed by O(n^2)
On Wed, Nov 23, 2011 at 12:50 AM, Aamir Khan <ak4u2...@gmail.com> wrote: > > > On Tue, Nov 22, 2011 at 11:50 PM, tech coder <techcoderonw...@gmail.com>wrote: > >> here is an O(n) approach using a stack. >> >> problem can be stated as " find the 1st smaller element on the right. >> >> put the first element in stack. >> take next element suppose "num" if this number is less than elements >> stored in stack, pop those elements , for these pooped elements num will >> be the required number. >> put the the element (num) in stack. >> >> repeat this. >> >> at last the elements which are in next , they will have 0 (valaue) >> >> @techcoder : If the numbers are not in sorted order, What benefit the > stack would provide ? So, are you storing the numbers in sorted order > inside the stack ? > > I can think of this solution : > > Maintain a stack in which the elements will be stored in sorted order. Get > a new element from array and lets call this number as m. Push m into the > stack. Now, find all elements which are <= (m-1) using binary search. Pop > out all these elements and assign the value m in the output array. Elements > remaining at the end will have the value 0. > > I am not sure about the complexity of this algorithm... > > >> On Wed, Nov 23, 2011 at 12:02 AM, Anup Ghatage <ghat...@gmail.com> wrote: >> >>> I can't think of a better than O(n^2) solution for this.. >>> Any one got anything better? >>> >>> >>> >>> On Tue, Nov 22, 2011 at 8:23 PM, Ankuj Gupta <ankuj2...@gmail.com>wrote: >>> >>>> Input: A unsorted array of size n. >>>> Output: An array of size n. >>>> >>>> Relationship: >>>> >>>> > elements of input array and output array have 1:1 correspondence. >>>> > output[i] is equal to the input[j] (j>i) which is smaller than >>>> input[i] and jth is nearest to ith ( i.e. first element which is smaller). >>>> > If no such element exists for Input[i] then output[i]=0. >>>> >>>> Eg. >>>> Input: 1 5 7 6 3 16 29 2 7 >>>> Output: 0 3 6 3 2 2 2 0 0 >>>> >>>> -- >>>> 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. >>>> >>>> >>> >>> >>> -- >>> Anup Ghatage >>> >>> -- >>> 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. >>> >> >> >> >> -- >> * >> >> Regards* >> *"The Coder"* >> >> *"Life is a Game. The more u play, the more u win, the more u win , the >> more successfully u play"* >> >> -- >> 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. >> > > > > -- > Aamir Khan | 3rd Year | Computer Science & Engineering | IIT Roorkee > > > -- > 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. > -- Anup Ghatage -- 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.
