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 597 / 602 1300
Distance query 530 / 543 1400
Robot on tree 448 / 474 1400
Heaviest edge 430 / 437 1500
Equal path 326 / 348 1500
Triplet 286 / 291 1500
Path update 332 / 340 1600
Second best minimum spanning tree 166 / 262 1700
Oggy and the cockroaches 59 / 88 1800