Gurobi 5.0.1 (linux64) logging started Fri Jan 18 07:08:10 2013

Optimize a model with 68 rows, 4160 columns and 52122 nonzeros
Presolve removed 22 rows and 120 columns
Presolve time: 0.31s
Presolved: 46 rows, 4040 columns, 48078 nonzeros
Variable types: 4020 continuous, 20 integer (20 binary)

Root relaxation: objective 4.810927e+03, 24 iterations, 0.00 seconds

    Nodes    |    Current Node    |     Objective Bounds      |     Work
 Expl Unexpl |  Obj  Depth IntInf | Incumbent    BestBd   Gap | It/Node Time

     0     0 4810.92679    0   16          - 4810.92679     -      -    0s
     0     0 4811.83742    0   16          - 4811.83742     -      -    0s
     0     0 4812.04713    0   16          - 4812.04713     -      -    0s
     0     0 4812.12387    0   16          - 4812.12387     -      -    0s
     0     0 4829.77118    0   12          - 4829.77118     -      -    0s
     0     0 4829.77118    0   12          - 4829.77118     -      -    0s
     0     0 4829.77118    0   12          - 4829.77118     -      -    1s
     0     0 4829.77662    0   12          - 4829.77662     -      -    1s
     0     0 4829.78372    0   12          - 4829.78372     -      -    1s
     0     0 4830.72922    0   10          - 4830.72922     -      -    1s
     0     0 4830.72922    0   10          - 4830.72922     -      -    1s
H    0     0                    4832.5416613 4830.72922  0.04%     -    1s
     0     2 4830.84877    0    9 4832.54166 4830.84877  0.04%     -    1s
*    6     5               6    4831.3317518 4830.84877  0.01%   5.7    1s

Cutting planes:
  Flow cover: 5

Explored 7 nodes (322 simplex iterations) in 1.54 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 4.831331751753e+03, best bound 4.830848770403e+03, gap 0.0100%