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 232 / 236 1300
Distance query 204 / 209 1400
Robot on tree 166 / 181 1400
Heaviest edge 158 / 162 1500
Equal path 120 / 125 1500
Triplet 99 / 102 1500
Path update 122 / 124 1600
Second best minimum spanning tree 51 / 94 1700