#1442. [Poi2006]Crystal

题目描述

输入格式

每一行给出数字N,2<=N<=50 下面一行给出N个数字.每个数字在[1,2^32-1]

输出格式

样例

样例输入

3  

2 1 3  

样例输出

5  

And the following are every possible numbers of atoms of each particular element:  

(0, 1, 1), (1, 0, 1), (1, 1, 0), (2, 0, 2), (2, 1, 3).

数据范围与提示