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Lazy DFAs (2010) are a clever optimization to mitigate the O(2^m) blowup of DFA construction, by only constructing the states that you actually visit. lazy DFAs reduce the theoretical automata construction time to either O(2^m) or O(n), whichever is lower. you could argue that it’s theoretically no longer linear time, since you could have a regex that creates a new state for every character in the input, but in practice you will keep revisiting the same states. for all intents and purposes it behaves more like O(n) with some initial wind-up time. the main downside of lazy DFAs is that they are more complex to implement, and you have to ship a compiler as part of your regex algorithm. i want to highlight Rust regex and RE2 as excellent implementations of this approach, which you can also see in the benchmarks.。PDF资料是该领域的重要参考
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Андрей Яшлавскийполитолог, ведущий научный сотрудник ИМЭМО РАН。业内人士推荐体育直播作为进阶阅读
Homeland security secretary was grilled in Senate hearing over immigration enforcement crackdown in Twin Cities
Владислав Уткин