!
! A 3 warehouse, 4 customer transportation model:
!
! XWH<i>C<j> = amount shipped from warehouse <i> to customer <j>
!
 MIN     6 XWH1C1 + 2 XWH1C2 + 6 XWH1C3 + 7 XWH1C4 
      +  4 XWH2C1 + 9 XWH2C2 + 5 XWH2C3 + 3 XWH2C4
      +  8 XWH3C1 + 8 XWH3C2 +   XWH3C3 + 5 XWH3C4
 SUBJECT TO
!
!  Demand constraints:
 C1)  XWH1C1 + XWH2C1 + XWH3C1 >=   15
 C2)  XWH1C2 + XWH2C2 + XWH3C2 >=   17
 C3)  XWH1C3 + XWH2C3 + XWH3C3 >=   22
 C4)  XWH1C4 + XWH2C4 + XWH3C4 >=   12
!
!  Supply constraints:
 WH1)  XWH1C1 + XWH1C2 + XWH1C3 + XWH1C4 <=   30
 WH2)  XWH2C1 + XWH2C2 + XWH2C3 + XWH2C4 <=   25
 WH3)  XWH3C1 + XWH3C2 + XWH3C3 + XWH3C4 <=   21
 END
! The objective should be 161.
