Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:14:27 2013

Optimize a model with 572 rows, 27092 columns and 54132 nonzeros
Presolve time: 0.04s
Presolved: 572 rows, 27092 columns, 54132 nonzeros
Variable types: 27040 continuous, 52 integer (52 binary)

Root relaxation: objective 6.808424e+04, 1562 iterations, 0.04 seconds

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

     0     0 68084.2411    0    4          - 68084.2411     -      -    0s
H    0     0                    68855.000000 68084.2411  1.12%     -    0s
H    0     0                    68571.000000 68084.2411  0.71%     -    0s
     0     0 68348.1429    0    2 68571.0000 68348.1429  0.33%     -    0s
     0     0 68355.9000    0    2 68571.0000 68355.9000  0.31%     -    0s
     0     0 68355.9000    0    2 68571.0000 68355.9000  0.31%     -    0s
     0     0 68355.9000    0    2 68571.0000 68355.9000  0.31%     -    0s
H    0     0                    68404.000000 68355.9000  0.07%     -    0s
     0     0 68355.9000    0    2 68404.0000 68355.9000  0.07%     -    0s
     0     0 68398.7778    0    1 68404.0000 68398.7778  0.01%     -    0s

Cutting planes:
  Implied bound: 14
  Flow cover: 4

Explored 0 nodes (2771 simplex iterations) in 0.57 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 6.840400000000e+04, best bound 6.839877777778e+04, gap 0.0076%