Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:36:26 2013

Optimize a model with 37881 rows, 37271 columns and 148901 nonzeros
Presolve removed 2664 rows and 0 columns
Presolve time: 0.22s
Presolved: 35217 rows, 37271 columns, 143573 nonzeros
Variable types: 37210 continuous, 61 integer (61 binary)

Root relaxation: objective 6.972302e+04, 6107 iterations, 0.68 seconds

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

     0     0 69723.0208    0    3          - 69723.0208     -      -    0s
H    0     0                    69947.000000 69723.0208  0.32%     -    1s
H    0     0                    69797.000000 69723.0208  0.11%     -    1s
     0     0 69723.6172    0    4 69797.0000 69723.6172  0.11%     -    1s
     0     0 69723.6172    0    3 69797.0000 69723.6172  0.11%     -    2s
     0     0 69723.6602    0    4 69797.0000 69723.6602  0.11%     -    2s
     0     2 69730.4333    0    4 69797.0000 69730.4333  0.10%     -    2s

Cutting planes:
  Gomory: 1
  Flow cover: 2

Explored 3 nodes (8259 simplex iterations) in 2.89 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 6.979700000000e+04, best bound 6.979263634229e+04, gap 0.0063%