摘要： Given a list of points that form a polygon when joined sequentially, find if this polygon is convex (Convex polygon definition). 阅读全文

摘要： Consider the string s to be the infinite wraparound string of "abcdefghijklmnopqrstuvwxyz", so s will look like this: "...zabcdefghijklmnopqrstuvwxyza 阅读全文

摘要： Define S = [s,n] as the string S which consists of n connected strings s. For example, ["abc", 3] ="abcabcabc". On the other hand, we define that stri 阅读全文