Because if you did what I suggested with the list, the time to look up the key would be linear in the length of the list. You'd have to look at each element until you found the key.

字典是用一种很神奇的，叫做散列法的算法,来实现的，后面我们将,会学到一点关于。

麻省理工公开课 - 计算机科学及编程导论课程节选

Dictionaries are implemented using a magic technique called hashing, which we'll look at a little bit later in the term, which allows us to retrieve keys in constant time.

散列法的内容,此方法可以让我们在线性,时间内检索到键,因此字典的大小并不重要了。

麻省理工公开课 - 计算机科学及编程导论课程节选