Gurobi 5.0.1 (linux64) logging started Fri Jan 18 07:08:14 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 3.881594e+03, 23 iterations, 0.00 seconds

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

     0     0 3881.59364    0    8          - 3881.59364     -      -    0s
     0     0 3881.86365    0    8          - 3881.86365     -      -    0s
     0     0 3881.97233    0    8          - 3881.97233     -      -    0s
     0     0 3882.08459    0    8          - 3882.08459     -      -    0s
     0     0 3882.33064    0    8          - 3882.33064     -      -    0s
     0     0 3882.34154    0    8          - 3882.34154     -      -    0s
     0     0 3882.34154    0    8          - 3882.34154     -      -    0s
     0     2 3882.34238    0    8          - 3882.34238     -      -    1s
*   80    22              18    3901.8979726 3883.01305  0.48%   2.5    1s
*   90    14              11    3894.3281888 3884.17422  0.26%   2.5    1s
*   94    13              13    3894.1331068 3884.17422  0.26%   2.5    1s
*  113     9               7    3893.9001900 3886.16647  0.20%   2.7    1s

Cutting planes:
  Implied bound: 3
  Flow cover: 16

Explored 127 nodes (435 simplex iterations) in 1.59 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 3.893900189954e+03, best bound 3.893708590568e+03, gap 0.0049%