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 235 / 239 1300
Distance query 208 / 213 1400
Robot on tree 169 / 184 1400
Heaviest edge 161 / 165 1500
Equal path 122 / 127 1500
Triplet 100 / 103 1500
Path update 123 / 126 1600
Second best minimum spanning tree 51 / 95 1700