Earlier theories-- it's wonderful to have scientific theories that you can use to handle these problems, which you cannot demonstrate any fact for whatsoever.

更早些的理论...,幸好我们还有些科学理论,可以用来处理这些问题,这些没有实例,可以证明的问题

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Now, it's also the case that this is fundamentally what class this algorithm falls into, it is going to take exponential amount of time.

哪个种类的一个实例,这个问题的时间复杂度是指数级的，也就是当n上升的时候。

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