Gurobi 5.0.1 (linux64) logging started Wed Dec 19 18:31:23 2012

Optimize a model with 3722 rows, 3721 columns and 16569 nonzeros
Presolve removed 3344 rows and 2214 columns
Presolve time: 0.07s
Presolved: 378 rows, 1507 columns, 4673 nonzeros
Variable types: 57 continuous, 1450 integer (1450 binary)

Root relaxation: objective 5.328039e+02, 206 iterations, 0.00 seconds

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

     0     0  532.80387    0   38          -  532.80387     -      -    0s
     0     0  539.67581    0   39          -  539.67581     -      -    0s
     0     0  540.33333    0   26          -  540.33333     -      -    0s
     0     0  540.33333    0   26          -  540.33333     -      -    0s
     0     0  540.33333    0   19          -  540.33333     -      -    0s
     0     2  541.00000    0   19          -  541.00000     -      -    0s
*  115    61               9     555.0000000  541.06465  2.51%   8.0    0s
H  280   108                     554.0000000  542.00000  2.17%   6.6    0s
*  325   111              10     552.0000000  542.00000  1.81%   6.9    0s
H  611   139                     551.0000000  544.11111  1.25%   6.4    0s

Cutting planes:
  Gomory: 5
  Implied bound: 1
  Clique: 2
  GUB cover: 1
  Zero half: 1

Explored 770 nodes (6242 simplex iterations) in 0.89 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 5.510000000000e+02, best bound 5.510000000000e+02, gap 0.0%