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

That one's not so obvious. So let's think about this for a second. To sort a list in linear time, would say, I have to look at each element in the list at most a constant number of times.

所以让我们来思考一会,要在线性时间能排序，列表里每个元素最多被使用常数次,不一定是一次，对吧。

麻省理工公开课 - 计算机科学及编程导论课程节选

How long does it take me to find the k'th element? Linear. Because I've got to walk my way down it. OK? So in this case, you have linear access. Oh fudge knuckle.

线性的！因为我得从头,向下走一步步走,所以这里是线性访问，哦，有问题了吧。

麻省理工公开课 - 计算机科学及编程导论课程节选

I've got to count my way down, which means that the access would be linear in the length of the list to find the i'th element of the list, and that's going to increase the complexity.

的位置并去访问，然后继续下去，也就意味着,找到数组中的第i个元素的方法,是关于数组的长度呈线性复杂度的，这回增加算法的复杂度。

麻省理工公开课 - 计算机科学及编程导论课程节选