Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:43:40 2013

Optimize a model with 40383 rows, 39753 columns and 158823 nonzeros
Presolve removed 3673 rows and 0 columns
Presolve time: 0.24s
Presolved: 36710 rows, 39753 columns, 151477 nonzeros
Variable types: 39690 continuous, 63 integer (63 binary)

Root relaxation: objective 6.688799e+04, 7059 iterations, 1.06 seconds

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

     0     0 66887.9878    0    4          - 66887.9878     -      -    1s
H    0     0                    68413.000000 66887.9878  2.23%     -    1s
     0     0 66890.0463    0    5 68413.0000 66890.0463  2.23%     -    1s
     0     0 66890.2024    0    5 68413.0000 66890.2024  2.23%     -    2s
     0     2 66893.7542    0    5 68413.0000 66893.7542  2.22%     -    3s
H    1     1                    68193.995035 66893.7542  1.91%   0.0    3s
H    2     2                    67642.762183 66954.1549  1.02%  82.0    3s
H    8     7                    67503.111111 67003.4315  0.74%  58.2    3s
H   10     8                    67472.000000 67003.4315  0.69%  67.0    3s
H   12     6                    67191.000000 67003.4315  0.28%  62.6    3s
H   16     7                    67151.000000 67003.4315  0.22%  55.0    4s
*   17     6              17    67135.000000 67003.4315  0.20%  53.4    4s
*   18     4               2    67121.000000 67015.3570  0.16%  60.0    4s

Cutting planes:
  Gomory: 1
  Flow cover: 3

Explored 23 nodes (8572 simplex iterations) in 4.35 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 6.712100000000e+04, best bound 6.712100000000e+04, gap 0.0%