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Just for kicks, here is the same implemented in Ruby. I noticed that the original page has a bug you fixed - towards the end of the main loop, there is:
if ($low > $n_las) { $n_las++; }
While in the pseudocode it's "if (low .ge. n_as) n_as += 1" and I presume .ge. means "greater or equal" ?!

Anyways, here's my implementation. It is notably cleaner than yours, but twice slower:

def find_lis_greedy(seq) n = seq.length terminals = [0] * (n + 1) backptrs = [-1] + [0] * (n - 1) lis = [] n_lis = 1 1.upto(n - 1) do |i| low = 1 high = n_lis while low <= high mid = (low + high) / 2 if seq[i] <= seq[terminals[mid]] high = mid - 1 else low = mid + 1 end end terminals[low] = i if low <= 1 backptrs[i] = -1 else backptrs[i] = terminals[low - 1] end n_lis += 1 if low > n_lis end lis[n_lis - 1] = seq[terminals[n_lis]] temp = terminals[n_lis] (n_lis - 2).downto(0) do |i| temp = backptrs[temp] lis[i] = seq[temp] end return lis end

In reply to Re^2: Puzzle: Longest Increasing Sequence by spurperl
in thread Puzzle: Longest Increasing Sequence by TedPride

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    [Discipulus]: Eily tongue twister or votes? ;=)
    [Eily]: Discipulus turn me into a Bishop
    Discipulus abracadabra.. Eily tranformed into a.. shop for bisexual peoples..
    [LanX]: Eily don't be sad ... you are the Bishop of our hearts.
    [marto]: 1nickt, I just said that in a Sean Connery accent
    [LanX]: Discipulus++ # Bi-Shop
    [Eily]: is the Bishop of hearts higher or lower ranked than the Jack?
    [ambrus]: Higher.
    [Eily]: Discipulus what's the merchandise? Other bi-people?
    [1nickt]: marto would like to hear that. Of course he speaks very deliberately and dramatically, allowing pauses between words, so if anybody could pull it off it would be him, or someone impersonating him ...

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