Format of the instances
Number of vehicles (m), number of bases (b), number of item types (n).
For each vehicle i (i = 1, ..., m):
Capacity (ci)
For each vehicle i (i = 1, ..., m):
For each base k (k = 1, ..., b):
Assignment cost (qik)
For each item type j (j = 1, ..., n):
Profit (pj) and weight (wj)
For each base k (k = 1, ..., b):
For each item type j (j = 1, ..., n):
Availability (akj)
For each item type j (j = 1, ..., n):
Demand lower bound (lj) and upper bound (uj)