Retrieve the list of variables that participate in an SOS constraint,
and the associated coefficients. The return value is the length of
this list. Note that the argument arrays must be long enough to
accommodate the result. Call the method with
arguments to determine the appropriate array lengths.
sos: The SOS set of interest.
vars: A list of variables that participate in sos. Can be null.
weights: The SOS weights for each participating variable. Can be null.
type: The type of the SOS set (either GRB.SOS_TYPE1 or GRB.SOS_TYPE2) is returned in type.
The number of entries placed in the output arrays. Note that you should consult the return value to determine the length of the result; the arrays sizes won't necessarily match the result size.