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 696 / 703 1300
Distance query 610 / 625 1400
Robot on tree 525 / 552 1400
Heaviest edge 489 / 496 1500
Equal path 376 / 397 1500
Triplet 347 / 352 1500
Path update 387 / 397 1600
Second best minimum spanning tree 199 / 306 1700
Oggy and the cockroaches 85 / 119 1800