Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:36:20 2013

Optimize a model with 37881 rows, 37271 columns and 148901 nonzeros
Presolve removed 3149 rows and 0 columns
Presolve time: 0.22s
Presolved: 34732 rows, 37271 columns, 142603 nonzeros
Variable types: 37210 continuous, 61 integer (61 binary)

Root relaxation: objective 7.052050e+04, 7769 iterations, 1.17 seconds

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

     0     0 70520.4970    0    5          - 70520.4970     -      -    1s
H    0     0                    71922.000000 70520.4970  1.95%     -    1s
     0     0 70524.1339    0    7 71922.0000 70524.1339  1.94%     -    1s
     0     0 70524.1339    0    7 71922.0000 70524.1339  1.94%     -    2s
H    0     0                    71694.205387 70524.1339  1.63%     -    3s
H    0     0                    71512.000000 70524.1339  1.38%     -    3s
     0     2 70552.4773    0    7 71512.0000 70552.4773  1.34%     -    3s
H    3     3                    71285.008185 70609.7953  0.95%  68.3    3s
H    6     6                    71014.972973 70616.3421  0.56%  77.3    3s
*    7     7               7    70818.000000 70616.3421  0.28%  88.3    3s
H   14     7                    70787.000000 70621.7279  0.23%   101    4s
H   15     8                    70759.777778 70621.7279  0.20%  94.2    4s
*   16     9               6    70746.000000 70621.7279  0.18%  89.0    4s

Cutting planes:
  Gomory: 2
  Flow cover: 3

Explored 30 nodes (9753 simplex iterations) in 4.39 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 7.074600000000e+04, best bound 7.074600000000e+04, gap 0.0%