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 438 / 444 1300
Distance query 395 / 405 1400
Robot on tree 325 / 349 1400
Heaviest edge 309 / 315 1500
Equal path 243 / 255 1500
Triplet 207 / 210 1500
Path update 230 / 236 1600
Second best minimum spanning tree 115 / 191 1700
Oggy and the cockroaches 34 / 55 1800