Tutorial on LCA algorithm. We use Binary Lifting to get O(N*log(N)) preprocessing and O(log(N)) to find the lowest common ancestor of two nodes in a tree.
Binary Lifting video [ Ссылка ]
SPOJ problem [ Ссылка ]
code [ Ссылка ]
Two homework problems:
1) Answer queries "find distance between two given nodes U and V" [ Ссылка ]
2) Given a tree with weighted edges (i.e. every edge has some value), answer queries "given two nodes U and V, find minimum weight along path U-V". (I don't have a source for this one).
Coding live streams - [ Ссылка ]
FAQ - [ Ссылка ]
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