Talk:Longest increasing subsequence

message: could someone who knows this topic add more on the O(nlgn) solution please
: See the patience sorting if you want one, but beware that it requires TOTAL ordering of the sequence (as opposed to the general graph-style weak ordering). BTW, this article needs to be improved to clearly separate the two cases. --BACbKA 17:51, 12 May 2006 (UTC)
thread_title:  Request 

message: "Though this is asymptotically equivalent to the longest-common subsequence version of the solution, the constant is lower, as there is less overhead."
Yeah, but I don't think the memory overhead is asymptotically equivalent.  If you have confidence that I'm right, please edit in a comment to that effect. 128.113.96.109 18:28, 31 March 2006 (UTC)
thread_title:  Dynamic Programming Comment 

message: There could be code for a similar algorithm that appears that way.  However, it isn't actually a demo of the code presented because it presents actual subsequences of the X[i] whereas the pseudo-code is dealing in index values M[j] and P[j].  Indeed, subtleties about the P[j] disappear completely, so the construction of the sequence at the end of the code is not even present.  (Indeed the data it requires cannot even be inferred from the GIF.)  Furthermore, the 'demo' seems to imply a storage requirement that is O(N^2), whereas, for the code, it is only O(N). I think there should at least be a comment somewhere to the effect that what the GIF presents are the actual complete subsequences for each length, as opposed to what the code really maintains, namely the indices for the last two elements of each such subsequence. DrHow (talk) 21:27, 11 August 2020 (UTC)
thread_title:  The animated GIF labeled "Demo of the code" is confusing. 

message: Let us suppose that output of the algorithm is of length k. Strictly speaking, the complexity of algo is O(n log k). We should discuss this output sensitivity in the article to explain the subtleties of the algo. What do you people say ??   —Preceding unsigned comment added by Msjaiswal (talk • contribs) 22:11, 29 November 2010 (UTC)
replies: text: I agree. To be more accurate, the page should mention the complexity as O(n log k) and not O(n log n). 117.211.88.150 (talk) 22:28, 6 July 2011 (UTC)
thread_title:  Output Sensitivity 

message: To be truly useful, this article needs a concrete example. -- 172.191.26.146 (talk) 17:35, 26 February 2009 (UTC)
thread_title:  Example, please 

message: Could somebody pls explain how the binary search works? X is not sorted, so I am not sure how to use binary search on it.--Jirka6 (talk) 18:29, 21 April 2009 (UTC)
replies: text: As the article states, the sequence X[M[1]], X[M[2]], ..., X[M[L]] is sorted. —David Eppstein (talk) 20:14, 21 April 2009 (UTC)

text: X[1], X[2], X[3], ... is not sorted. X[M[1]], X[M[2]], X[M[3]], ... is a sorted subsequence. The binary search is in the sorted subsequence, not in the whole sequence. —David Eppstein (talk) 05:12, 7 November 2009 (UTC)

text: Well there's your problem. M[i] is not the position of the end of the *first* subsequence of length i. It is the position of the end of the subsequence of length i that has the smallest possible end value. —David Eppstein (talk) 07:46, 8 March 2012 (UTC)
thread_title:  Binary search? 

message: Yes, I also think the algorithm should be outlined, as well as a word
about the asymptotic performance (It is in the order of 2Sqrt(n) for random sequences of length n). Also, the corresponding online problem is equally important for applications(online monotone subsequence problem means that the monotone sequence must be selected on sequential observation without recall on preceding numbers)
Optimal rules for the sequential selection of monotone subsequences of maximum expected length yield, interestingly, still asymptotically in expectation Sqrt(2n).
81.247.74.101 (talk) 19:55, 18 May 2009 (UTC)
thread_title: More useful information required

message: The pseudo-code mixes up array index numbering.
For instance, it declares M to be from M[1], M[2] etc., but inside the program it starts zero-indexing with j=0.
Somebody should fix this.
Andares (talk)
: Go ahead, be bold!  Fix the problem! :) See: WP:SOFIXIT Jwesley78 18:25, 5 April 2010 (UTC)
thread_title:  Pseudo-code 

message: It says that P is the predecessor of X. Can someone explain this more fully?  — Preceding unsigned comment added by 96.236.148.28 (talk) 16:12, 27 October 2011 (UTC)
thread_title:  Explain the P[] Array 

message: Code is basicly patience sort, and description has nothing to do with code
I suspect fraud against wikipedia users, on this ground.
I ask wikipedia administrator to check and fix this.  — Preceding unsigned comment added by 2001:2020:331:F0DB:599D:553D:4E8F:5A1A (talk) 17:31, 20 August 2023 (UTC)
thread_title:  Code is basicly patience sort, and description has nothing to do with code 

message: Article is really bad, because its focus on personal opinion of "best" algorithm. 
This is unwanted approach from wikipedia point of view. 
One should instead give a overview over different approaches; what is done before, to make it easier for others to get a overview over the subject.
Different appraoches is many: pasience sort, segment tree, and dynamic programing. Each of these algorithms has strength and weaknesses, and one should
not rule out them due to rapid changes in computer architectures and waste range of different computer architectures.
Most of structure in article is bad, and should be fixed. Young tabular should be explained in context of patience sort, and not out of context, because it can be used to give insight to patience sort.  — Preceding unsigned comment added by 2001:2020:307:CBAE:7462:DCE2:86F7:818D (talk) 17:42, 21 August 2023 (UTC)
thread_title:  Bad structure and bad approach to just talk about "best" algorithm