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 551 / 556 1300
Distance query 493 / 504 1400
Robot on tree 412 / 437 1400
Heaviest edge 393 / 400 1500
Equal path 302 / 320 1500
Triplet 261 / 266 1500
Path update 305 / 312 1600
Second best minimum spanning tree 156 / 246 1700
Oggy and the cockroaches 54 / 83 1800