Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:36:41 2013

Optimize a model with 37881 rows, 37271 columns and 148901 nonzeros
Presolve removed 3091 rows and 0 columns
Presolve time: 0.22s
Presolved: 34790 rows, 37271 columns, 142719 nonzeros
Variable types: 37210 continuous, 61 integer (61 binary)

Root relaxation: objective 5.462353e+04, 5503 iterations, 0.75 seconds

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

     0     0 54623.5331    0    5          - 54623.5331     -      -    1s
H    0     0                    55637.000000 54623.5331  1.82%     -    1s
H    0     0                    55034.000000 54623.5331  0.75%     -    1s
     0     0 54626.1994    0    6 55034.0000 54626.1994  0.74%     -    1s
     0     0 54626.1994    0    6 55034.0000 54626.1994  0.74%     -    1s
     0     0 54626.1994    0    5 55034.0000 54626.1994  0.74%     -    3s
     0     0 54626.2780    0    6 55034.0000 54626.2780  0.74%     -    3s
     0     0 54626.2780    0    6 55034.0000 54626.2780  0.74%     -    3s
     0     2 54628.5231    0    6 55034.0000 54628.5231  0.74%     -    4s
H    9     6                    55000.380952 54764.6203  0.43%  46.1    4s
*   11     7               9    54886.000000 54764.6203  0.22%  51.1    4s
    13     5 54842.6388    1    5 54886.0000 54792.5518  0.17%  62.8    5s
*   19     1               4    54838.000000 54833.0000  0.01%  50.5    5s

Cutting planes:
  Gomory: 2
  Flow cover: 6

Explored 20 nodes (9502 simplex iterations) in 5.12 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 5.483800000000e+04, best bound 5.483300000000e+04, gap 0.0091%