If I look for, say, minus 1, you might go, gee, wait a minute, if I was just doing linear search, I would've known right away that minus one wasn't in this list, because it's sorted and it's smaller than the first elements.
如果我要查找-1,你可能要怒了,呵呵,等一等,如果我用的是线性查找,我不会知道-1不在这个列表中,但是列表是排好序的,1又比第一个元素小。
On the other hand, if I want to sort it first, OK, if I want to do sort and search, I want to sort it, it's going to take n log n time to sort it, and having done that, then I can search it in log n time.
我先排序,好的,如果我想排序再搜索,我要排序,这需要花n,log,n时间排序,然后做完了,我们能花log,n时间搜索,啊,哪一种更好呢?恩,呵呵。
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