Data structure for collection of strings with prefix and suffix queries

Question

I need a proper data structure for a collection of strings. Users may query for the current number of strings in the collection that have a certain prefix or suffix, and subsequently remove these strings from the collection if they choose to. Users may also insert one string; if a string is inserted more than once, it should be returned multiple times.

The time complexity of query operations should be O(m + log n), where m is the expected size of the result of the operation.

I am thinking of using a Trie but we will have to use 2 tries one for the suffix and another for prefix, the problem with the approach is we won't be able to apply remove() in required time in that case.

Evgeny Lazin · Accepted Answer · 2012-09-07 06:09:14Z

1

Data structure that you need is called trie, or prefix tree. You can combine two prefix trees, one containing original strings and another, containing inverted strings. Searching must be performed on one of the prefix trees, depends on what you need - suffix or prefix. With this data structure you can search not only by suffix and prefix, you can find strings, that contains arbitrary substring.

answered Sep 7, 2012 at 6:09

Evgeny Lazin

9,4636 gold badges52 silver badges86 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Data structure for collection of strings with prefix and suffix queries

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related