The victory was a remarkable comeback for Ms. Tsai and suggested that Beijing’s pressure campaign had backfired.
来自 2014 年信息学奥林匹克中国国家队候选队员作业。
Hat puzzles are logic problems that date back to as early as 1961. Such hat puzzles, frequently contextualized as prisoners and hats puzzles, are induction puzzles (a kind of logic puzzle) that involve reasoning about the actions of other people, drawing in aspects of Game theory sometimes called the hierarchy of beliefs. There are many variations, but the central theme remains the same.
IOI 2018 Day 1 T1，交互题。
细节很多的树形 DP + 贪心 + 二分。