1. This allows for the runtime behavior to be linear, but has the downside of relatively large memory requirements, potentially multiple times the size of the input source.
    这决定了Packrat解析的时间复杂度是线性的，但是缺点是需要很大的内存，通常是源代码大小的几倍。

2. Packrat parsing solves the problem of this kind of parser, i. e. exponential parse time.
    Packrat解析解决了诸如指数级解析时间的问题。