Module Lowest common ancestor (LCA)

Lowest common ancestor (LCA)

**Frequency: 8/10** In many cases where a problem involves querying a path on a tree, there is a high likelihood that the Lowest Common Ancestor (LCA) will be a crucial element in the solution. There are also a lot of problems involving LCA in the next module, Euler tour.

Resources

- [CP Algorithms: Lowest Common Ancestor - Binary Lifting](https://cp-algorithms.com/graph/lca_binary_lifting.html)

Problems

LCA 602 / 607 1300
Distance query 534 / 547 1400
Robot on tree 449 / 475 1400
Heaviest edge 431 / 438 1500
Equal path 327 / 349 1500
Triplet 287 / 292 1500
Path update 333 / 341 1600
Second best minimum spanning tree 167 / 264 1700
Oggy and the cockroaches 59 / 88 1800