Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:20:05 2013

Optimize a model with 30855 rows, 30305 columns and 121055 nonzeros
Presolve removed 3401 rows and 0 columns
Presolve time: 0.18s
Presolved: 27454 rows, 30305 columns, 114253 nonzeros
Variable types: 30250 continuous, 55 integer (55 binary)

Root relaxation: objective 5.553354e+04, 4151 iterations, 0.45 seconds

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

     0     0 55533.5397    0    5          - 55533.5397     -      -    0s
H    0     0                    55989.000000 55533.5397  0.81%     -    0s
H    0     0                    55808.000000 55533.5397  0.49%     -    0s
H    0     0                    55635.000000 55533.5397  0.18%     -    0s
     0     0 55534.3713    0    6 55635.0000 55534.3713  0.18%     -    1s
     0     0 55534.3713    0    5 55635.0000 55534.3713  0.18%     -    1s
     0     0 55534.4526    0    6 55635.0000 55534.4526  0.18%     -    1s
     0     0 55534.4983    0    6 55635.0000 55534.4983  0.18%     -    1s
     0     0 55618.0588    0    1 55635.0000 55618.0588  0.03%     -    2s
H    0     0                    55621.000000 55618.0588  0.01%     -    2s

Cutting planes:
  Flow cover: 1

Explored 0 nodes (6572 simplex iterations) in 2.08 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 5.562100000000e+04, best bound 5.561805882353e+04, gap 0.0053%