Big topic: introduction ~ popularization

One last question: improve

Basic dfs, basic dynamic programming, basic string operation, basic number theory, basic graph theory, basic data structure algorithm

Knowing this, I almost saved one.

It will be a little more difficult to save the competition, but it will be a little more difficult for the national competition. Dfs+ pruning, dynamic programming (often test the number DP), character string (kmp), number theory (test the mathematical ability), graph theory (general and minimum spanning tree, shortest path combination test), data structure (there are too many, line tree, balanced tree, etc. )

Just brush a few more questions (one or two hundred, understand) and you will save one.