Module DP on tree

DP on tree

**Frequency: 6/10** DP, but on tree.

Resources

- [USACO: DP on trees](https://usaco.guide/gold/dp-trees?lang=cpp)

Problems

Tree coloring 429 / 448 1200
Tree coloring 2 365 / 368 1200
Maximum sum path 306 / 346 1300
Path with length k 295 / 303 1300
Subgraph 242 / 253 1300
Beautiful tree 215 / 221 1500
Company 169 / 177 1700
Zero tree 141 / 157 1700
Selfie 75 / 90 1800