题目网址: http://www.puzzleup.com/2015/
http://www.puzzleup.com/2015/puzzle/?3
答题时限: ８月13日７ＰＭ－比赛结束（约12月16日）
加分时限: ８月13日７ＰＭ－８月18日６：５９ＰＭ
答对可得基本分１００分。答案可上传５次，每改１次答案从基本分扣２０分。
比赛期间内可随时上传答案，加分时限内答对第ｎ天加（６－ｎ）分
另依题目的难易有额外加分（如有８０％的人这题答错，答对者加８０分）
◆HALF OF ITS SQUARE
All digits of a number are different and for each of its digits that has at
least two other digits on its right, the half of the square of that digit is
greater than the multiplication of the two digits immediately following on
its right.
What is the greatest number having this property?
有个数，各位数不同，且对每个右边有至少两位数的位数来说，
自己的平方的一半比右边邻接的两个位数的乘积要大。
试问此数最大多少？