Putting together everything we've done so far yields the following complete LINGO model:

MODEL:

MIN = @SUM( LINKS( I, J):

   COST( I, J) * VOLUME( I, J));

@FOR( VENDORS( J):

   @SUM( WAREHOUSES( I): VOLUME( I, J)) =

    DEMAND( J));

@FOR( WAREHOUSES( I):

   @SUM( VENDORS( J): VOLUME( I, J)) <=

    CAPACITY( I));

END

Model: WIDGETS

However, we still need to define sets of objects used in the model (vendors, warehouses and shipping arcs) as well as the data.  We will do this is two additional model sections called the sets section and the data section.