samsoom's blog

By samsoom, history, 9 months ago, In English

Hi,

Why isn't there a binary lifting/LCA tag? I mean it's an important topic, and I'm sure many questions can be solved using them. Can u pls add one?

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9 months ago, hide # |
 
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but trees , dfs and similar commonly involves it

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    9 months ago, hide # ^ |
     
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    True but there are a lot of questions that are solved purely by binary lifting/ lca. I js feel that it needs to be classified as a topic by itself

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      9 months ago, hide # ^ |
       
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      but something that I feel is that many topics if they are directly embedded in the topic section of the problem ,then the problem becomes very vague and less enjoyable . Also lca/lifting both involves dfs at a point , so dfs and 'similar ' already covers all the tree algorithms

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        9 months ago, hide # ^ |
         
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        Yes but when u want to grasp a topic well the best way to do it is to solve specific questions that include that topic. As for lca/lifting involving dfs, binary lifting has 0 dfs in it, and the dfs in lca is only used for the in/out time, the lca/lifting itself is nothing like dfs, they are super unrelated to each other

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          9 months ago, hide # ^ |
           
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          by theory , yes they are unrelated , but for learning part there are multiple other resources , USACO provides good questions topic wise .

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            9 months ago, hide # ^ |
             
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            Yes true, USACO does provide good questions. But at the end of the day we come to the same conclusion that LCA/binary lifting doesn't fall under the category of dfs and similar. Anyways idt they'll put a tag lol, but it was a good try nonetheless.

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9 months ago, hide # |
 
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even Cses, one of the most educational websites for cp doesn't have a list specially for lifting/LCA.

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    9 months ago, hide # ^ |
     
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    yea but they also don't have a shortest path list even though there's a shortest path tag on cf.