Translate (AKA immediate implementation problem)

1. The problem is obvious that it should just be some data structures

• Segment tree CF474-D2-F

1. Just DP, e.g. CF489-D2-F

Converting from brute force

1. Sometimes it just works ??? this works especially well if you notice the input is extremely small
2. Meet in the middle to be square root smaller CF525-D2-E CF1006-D3-F
3. Backtracking to prune states
4. Memoization (this is just dp lol)