SPOJ 2716. Maximal Quadrilateral Area (QUADAREA) with F#

Problem Definition

Details about this problem is available here.  Required Background Topic:  Cyclic quadrilateral.

Solution

Given that the length of the sides are {a,b,c,d}, the Maximal Quadrilateral Area is given by the following equation:

where semiperimeter s can be defined as follows.

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