_{This problem is a programming version of Problem 66 from projecteuler.net}

Consider quadratic Diophantine equations of the form:

For example, when , the minimal solution in is . It can be assumed that there are no solutions in positive integers when D is square.

By finding minimal solutions in for , we obtain the following:

Hence, by considering minimal solutions in for , the largest is obtained when .

Find the value of in minimal solutions of for which the largest value of is obtained.