Consider a problem of assigning N manufacture facilities to N locations. For each i,j, there are Cij amount of products to be transferred from facility i to facility j. If facility i is assigned to location k and facility j is assigned to location l, then the associated transfer cost is CijDkl, where Dkl represents the distance between location k and location l. how to assign each facility to one and only one location while minimizing the total cost.