Dear monks,

I have a little problem here. I also have a solution, but maybe someone has a better one. So the problem is as follows: I have a list of words like :

mamy
dady
bal
foo
bar
ymamaa
...
[download]

and i need to find out if there is a word which reverse can be matched to any other word in my set. Example:

    (reverse)   (match)
mamy   -> ymam    ->    ymamaa
[download]

The easiest solution here would be to create a reverse of every word, join them to the original set, label them , sort them (lex. of course). That way 'ymam' and 'ymamaa' would be one next to another and since I have labelled them I can say in O(c) (c=constant) time if there exists a match to the reverse of 'mamy' or not.

Does anyone have a better solution to this ??

Thank you,

Baxy

Update: Thnx chordoba that is true, but i missed out one simple detail. These sets are huge. Therefore regex-ing would take much longer then my sorting suggestion. But yes you are correct (++) Thnx

Update : Yes only from the start ! :) That is also a good solution , but trie's are a bit memory heavy wouldn't you say. so that is why I thought sorting is the simplest one plus building a trie takes in practice much longer then sorting. Wouldn't you say?

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