did you get the problem from a published book?

来源: bearsback 于 2010-01-15 13:47:53 [] [博客] [旧帖] [给我悄悄话] 阅读数 : (23 bytes)
回答: i believe that E is right 由 bearsback 于 2010-01-15 13:07:19

please list the source.

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