bhargav104's blog

By bhargav104, history, 6 years ago, In English

Why do we always break down a query into prefix query when the problem involves Persistent Segment tree is it not possible to directly query a range [L,R]? For example consider this problem and the editorial — http://www.codechef.com/SNCKEL16/problems/SEGSUMQ

If we sort the vectors by the angle and then insert into the persistent segment tree in that order when we get a query <C,D> we can just query that segment tree in which all the vectors in it have lesser angle.

Am i missing something here? Could use some help. Thanks :)

 
 
 
 
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6 years ago, # |
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Auto comment: topic has been updated by bhargav104 (previous revision, new revision, compare).

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6 years ago, # |
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Who told you that you should always break the queries into prefix queries.

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    6 years ago, # ^ |
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    It's just something that I've noticed in all the blogs and editorials related to this topic. Couldn't figure out why everyone always does it in the prefix query way.