Gurobi 5.0.1 (linux64) logging started Fri Jan 18 07:07:35 2013

Optimize a model with 4028 rows, 4044 columns and 16082 nonzeros
Presolve removed 2048 rows and 2050 columns
Presolve time: 0.10s
Presolved: 1980 rows, 1994 columns, 5962 nonzeros
Variable types: 1007 continuous, 987 integer (987 binary)

Root relaxation: objective 4.440467e+03, 798 iterations, 0.02 seconds

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

     0     0 4440.46714    0    1          - 4440.46714     -      -    0s
H    0     0                    4458.9449856 4440.46714  0.41%     -    0s
     0     0 4446.78799    0    1 4458.94499 4446.78799  0.27%     -    0s
     0     0 4446.78799    0    1 4458.94499 4446.78799  0.27%     -    0s
     0     0 4446.78799    0    1 4458.94499 4446.78799  0.27%     -    0s
     0     0     cutoff    0      4458.94499 4458.94499   0.0%     -    0s

Cutting planes:
  Implied bound: 1
  Flow cover: 3

Explored 0 nodes (954 simplex iterations) in 0.16 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 4.458944985630e+03, best bound 4.458944985630e+03, gap 0.0%