set O := IE_Junction, Centerville, Wayover_City Mockingbird;
set D := A_Station, Fine_Place, Goodville, Somewhere_Street;

# supply
param a :=
IE_Junction     4
Centerville     1
Wayover_City    2
Mockingbird     2;

# demand
param r :=
A_Station		3
Fine_Place		2
Goodville		0
Somewhere_Street        3;


param c :
                A_Station       Fine_Place      Goodville       Somewhere_Street :=
IE_Junction     13              35              42              9
Centerville     6               61              18              30
Wayover_City    15              10              5               9
Mockingbird	20		15		12		40;