120 - ZOJ Monthly, September 2012 - E
A n * m grid as follow:
Count the number of acute triangles, three of whose vertice must be grid-points.
The input consists of several cases. Each case consists of two positive integers n and m (1 ≤ n, m ≤ 100).
For each case, output the total number of acute triangle.
1 1 2 2
Author: WU, Yingxin