Gurobi 5.0.1 (linux64) logging started Fri Jan 18 01:40:21 2013

Optimize a model with 52 rows, 312 columns and 1906 nonzeros
Presolve removed 22 rows and 80 columns
Presolve time: 0.00s
Presolved: 30 rows, 232 columns, 1662 nonzeros
Variable types: 220 continuous, 12 integer (12 binary)
Found heuristic solution: objective 3896.0098800

Root relaxation: objective 3.881594e+03, 13 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    3 3896.00988 3881.59364  0.37%     -    0s
     0     0 3881.86365    0    3 3896.00988 3881.86365  0.36%     -    0s
     0     0 3881.86365    0    3 3896.00988 3881.86365  0.36%     -    0s
*    0     0               0    3893.8897177 3893.88972   0.0%     -    0s

Cutting planes:
  Gomory: 1
  Flow cover: 3

Explored 0 nodes (70 simplex iterations) in 0.02 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 3.893889717662e+03, best bound 3.893889717662e+03, gap 0.0%