And his eyes have all the seeming of a demon that is dreaming, And the lamp-light o'er him streaming throws his shadow on the floor;

VOA: special.2009.02.02

Here's the problem. How do I get to the nth- er, the k'th element in the list, in this case?

如何找到第n个元素呢-,在这里，如何找到第k个元素呢？

麻省理工公开课 - 计算机科学及编程导论课程节选

The direction is -er.

方向是 -er

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