Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:07:15 2013

Optimize a model with 23568 rows, 23088 columns and 92208 nonzeros
Presolve removed 2434 rows and 0 columns
Presolve time: 0.14s
Presolved: 21134 rows, 23088 columns, 87340 nonzeros
Variable types: 23040 continuous, 48 integer (48 binary)

Root relaxation: objective 5.299096e+04, 4029 iterations, 0.33 seconds

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

     0     0 52990.9554    0    4          - 52990.9554     -      -    0s
H    0     0                    53458.000000 52990.9554  0.87%     -    0s
     0     0 52993.5783    0    6 53458.0000 52993.5783  0.87%     -    0s
H    0     0                    53273.909091 52993.5783  0.53%     -    1s
H    0     0                    53271.000000 52993.5783  0.52%     -    1s
     0     2 53005.2941    0    6 53271.0000 53005.2941  0.50%     -    1s
H    3     3                    53169.392857 53043.9009  0.24%  59.3    1s
*    4     3               4    53086.000000 53043.9009  0.08%  55.0    1s

Cutting planes:
  Gomory: 2
  Flow cover: 2

Explored 6 nodes (4327 simplex iterations) in 1.73 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 5.308600000000e+04, best bound 5.308296712053e+04, gap 0.0057%