A transporter has to deliver heating oil from a refinery to a certain number of clients. The distances between the clients and the refinery and the demands in liters for the different sites are given. The transport company uses tankers with a capacity of 39000 liters for the deliveries. Determine the tours for delivering to all clients that minimize the total number of kilometers driven.

Further explanation of this example: 'Applications of optimization with Xpress-MP', Section 10.4 'Heating oil delivery' (e4deliver.mos)

! Data file for `vrp.mos'

DIST: [ 0 148 55  32  70 140 73
      148   0 93 180  99  12 72
       55  93  0  85  20  83 28
       32 180 85   0 100 174 99
       70  99 20 100   0  85 49
      140  12 83 174  85   0 73
       73  72 28  99  49  73  0]

DEM: [(2) 14000 3000 6000 16000 15000 5000]

CAP: 39000

POS: [[44 62] [183 68] [94 75] [11 54] [87 95] [175 56] [116 83]]