ITE stands for if-then-else. ITE([a-z], leaf(R1), leaf(R2)) means: “if the character is in [a-z], the derivative is R1, otherwise it’s R2”. these trees can nest, splitting the character space into finer partitions as needed. the key insight is that the derivative function never takes a character argument - it produces a complete map from all possible characters to their resulting states in one shot.
Овечкин продлил безголевую серию в составе Вашингтона09:40
，这一点在新收录的资料中也有详细论述
贯彻落实党中央《建议》明确的主要目标，《纲要（草案）》细化提出20项主要指标。经济发展方面，围绕增长、结构、效率提出3项指标。其中，综合考虑国内外形势和各方面因素，兼顾需要与可能，提出国内生产总值增长保持在合理区间、各年度视情提出，为到2035年人均国内生产总值比2020年翻一番、达到中等发达国家水平打好基础。创新驱动方面，围绕创新投入及其成效提出3项指标。其中，充分考虑研发投入增长趋势和企业投入能力，提出全社会研发经费投入年均增长7%以上，与“十四五”规划目标保持一致，确保研发投入力度不减。民生福祉方面，为更好解决人民群众急难愁盼问题，针对性提出就业、收入、教育、医疗、健康、“一老一小”等7项指标。绿色低碳方面，围绕降碳减污、生态环保等提出5项指标。其中，根据国家自主贡献目标，提出单位国内生产总值二氧化碳排放累计降低17%，继续推动重点领域绿色低碳转型。安全保障方面，围绕粮食、能源生产能力提出2项指标，着力夯实国家安全重要基础保障。
This is certainly what I see today. Up until the early 2010s, I’d often hear people say, “I like all kinds of music except for [subset of rap, heavy metal, country].” Today, that would be passé. If you ask people what kind of music they like, they often don’t want to name any genres, and if you force them, they’ll insist on naming ten.
The quadtree is the two-dimensional case of a broader family of space-partitioning data structures. Octrees extend the same idea to three dimensions (splitting cubes into eight children), KD-trees use alternating axis-aligned splits (splitting along x, then y, then x again), and R-trees group nearby objects into bounding rectangles. Each variant makes different tradeoffs between construction time, query speed, and update cost.