So, what's the idea? If I know what my hash function does, it maps, in this case characters into a range zero to 256, which is zero to 255, I create a list that long, and I simply mark things.

我知道我的哈希函数做什么,在这个例子中，它将字母，映射成0到255的256个数字，我创建了一个这么长的列表，并且我只是简单的标志这些东西。

麻省理工公开课 - 计算机科学及编程导论课程节选

Well, this question mark becomes an O, this question mark becomes an O, and then the loop terminates 0 1 2 because it's iterating from zero to N so that's zero, 1, 2 and the length of the string is 3 so the loop terminates, but I remember that I needed to have this special sentinel value so I'm just going to put it there manually.

嗯，这个问号变成了，这个问号变成了0，然后循环结束了,以为迭代从0到N，那就是，字符串的长度是3，然后循环就结束了，但是我记得我需要这个特殊的标记值,所以需要手动的加上它。

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