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 186 / 189 1300
Distance query 164 / 169 1400
Robot on tree 140 / 154 1400
Heaviest edge 134 / 138 1500
Equal path 97 / 101 1500
Triplet 70 / 72 1500
Path update 95 / 96 1600
Second best minimum spanning tree 32 / 67 1700