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 314 / 318 1300
Distance query 276 / 283 1400
Robot on tree 228 / 248 1400
Heaviest edge 209 / 215 1500
Equal path 162 / 171 1500
Triplet 134 / 138 1500
Path update 164 / 169 1600
Second best minimum spanning tree 75 / 130 1700
Oggy and the cockroaches 16 / 26 1800