Re: [algogeeks] Re: DP problems in SPOJ

2011-12-29 Thread kumar rajat
@Lucifer: Ya,got it now..thanks a lot! :) On Thu, Dec 29, 2011 at 7:43 AM, Lucifer sourabhd2...@gmail.com wrote: @rajat.. First of all.. sorry for the late reply :) Below i have explained the dp approach by taking.. Once u trace it u will be able to understand the code.. Lets denote the

Re: [algogeeks] Re: Find even length palindrome.

2011-12-29 Thread shady
given question is :- Given a string of length N, find whether there exits an even length palindrome substring. question is unclear, you want a palindrome whose substring of even length is present in the given string of length N, right ? where the palindrome is itself formed from the given

Re: [algogeeks] Re: Find even length palindrome.

2011-12-29 Thread atul anand
@shady : lets go with this one:- given string = *abcdrdcba abcd != dcba - not a palindrome **abcd != dcba - **not a palindrome * * *no even length palindrome found for the given string. given string = ab*cddc*abr even lenght palindrome found = cddc if another even length palindrome found

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@sumit How do u guarantee O(N) in.. T(n) = T(n/2) + O(n).. I don't think just searching from the middle would cover all the cases... Say u have array of size 20 partitioned in 2 subarrays of sizes 10 and 10.. Now from left subarray u have a plaindrome of some recorded length.. Similarly from

[algogeeks] Re: Obstacle Avoidance

2011-12-29 Thread SAMMM
I found something similar algorithm . one hich DFS and BFS algorithm :- one named Trémaux's algorithm uses DFS and for finding the shortest path it used Shortest path algorithm . Follow the link and find the these algorithms here .. http://en.wikipedia.org/wiki/Maze_solving_algorithm -- You

Re: [algogeeks] Re: Find even length palindrome.

2011-12-29 Thread atul anand
@Lucifer : in your first approach ... i guess outer loop should start from 1 and inner loop should move n to 1.. in the given algo both outer and inner loop move from N to 1. will your algo work for this case?? string = abccba i.e when given string itself is longest even length palindrome.

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@Editing mistake for the comment in the innermost 'If' loop.. We need *not check for the case where the reverse substring is placed before the orig substring as its symmetric.. On Dec 29, 7:12 pm, Lucifer sourabhd2...@gmail.com wrote: @shady I am re-posting the code.. Somehow the format is

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@atul The loop runs are correct.. Yes, it works fine for abccba giving out 6 as the max length of even palindrome which is nothing but the entire string.. On Dec 29, 4:16 pm, atul anand atul.87fri...@gmail.com wrote: @Lucifer : in your first approach ... i guess outer loop should start from

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@shady... The first approach with a slight modification will solve the above mentioned problem... I have modified the previous to show the same.. The innermost 'If' statement needs to be modified to ensure that the found substring which is present in both the originalStr and reverseStr doesn't

Re: [algogeeks] Re: Find even length palindrome.

2011-12-29 Thread shady
oh, i didn't read all the posts, anyway i have understood lucifier's O(n^2) time solution. and ya what's the solution for this question? Given a string of length N, find whether there exits an even length reverse substring of a substring. On Thu, Dec 29, 2011 at 2:23 PM, atul anand

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@shady... The first approach with a slight modification will solve the above mentioned problem... I have modified the previous to show the same.. The innermost 'If' statement needs to be modified to ensure that the found substring which is present in both the originalStr and reverseStr doesn't

Re: [algogeeks] Re: amazon ques

2011-12-29 Thread praveen raj
IT will grt help for me... if u all tell me.. mapstring,int m; m[topcoder]=2 My question is this: Is 2 is an key value??or index value of hash table...??... kindly explain how actual mapping is done... in hash table...plz... PRAVEEN RAJ DELHI COLLEGE OF ENGINEERING On Tue, Dec 27,

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@RAJ Can u explain ur dp approach... For ex- what is i and j in LP(i,j) ? On 29 Dec, 19:14, Lucifer sourabhd2...@gmail.com wrote: @Editing mistake for the comment in the innermost 'If' loop.. We need *not check for the case where the reverse substring is placed before the orig substring as

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@shady... The first approach with a slight modification will solve the above mentioned problem... I have modified the previous to show the same..  The innermost 'If' statement needs to be modified to ensure that the found substring which is present in both the originalStr and reverseStr doesn't

Re: [algogeeks] Frequency Sort Algo

2011-12-29 Thread praveen raj
steps: 1) use hash mapping to keep track of frequency of each and every element. 2)Then iterate hash table and store in 2D array with 1st column(element value) and 2nd column(frequency of element value). 3)sort the row according to second column(i.e frequency). 4)Then Print the

[algogeeks] Re: Find even length palindrome.

2011-12-29 Thread Lucifer
@shady I am re-posting the code.. Somehow the format is getting messed up... while ( pRev 0) { for ( pStrt = N; pStrt =1 ; --i) { if ( OrigStr[pStrt] == OrigStr[pRev] ) { X[pStrt] = 1 + X[pStrt - 1]; if ( (X[pStrt] % 2 == 0) (currMax X[pStrt])

Re: [algogeeks] Re: amazon ques

2011-12-29 Thread pankaj agarwal
same question as above with one more task is given 4) FindAnyElement() which will return any element present in that structure with O(1). for given all 4 task Please suggest which Data Structure is better now...? Best Regards, Pankaj Agarwal -- You received this message because you are

Re: [algogeeks] Re: Obstacle Avoidance

2011-12-29 Thread praveen raj
Procedure: 1.if out of boundary return 0; 2.If reach final point return 1. 3.if(next point has no obstacle then go for it.. recursively) PRAVEEN RAJ DELHI COLLEGE OF ENGINEERING -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this

[algogeeks] Determine if BST has single child for every node given pre order

2011-12-29 Thread top coder
Input : You have been given a sequence of integers. Now without actually constructing BST from the given sequence of integers (assuming the sequence is pre-order) determine if each node of BST has single child (either left or right but not both). Output : YES if given integer sequence