Gurobi 5.0.1 (linux64) logging started Tue Nov 20 05:55:19 2012

Optimize a model with 740 rows, 121 columns and 1480 nonzeros
Presolve removed 279 rows and 0 columns
Presolve time: 0.00s
Presolved: 461 rows, 121 columns, 1173 nonzeros
Variable types: 0 continuous, 121 integer (121 binary)
Found heuristic solution: objective 28.0000000

Root relaxation: objective 4.137395e+01, 325 iterations, 0.01 seconds

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

     0     0   41.37395    0  118   28.00000   41.37395  47.8%     -    0s
H    0     0                      31.0000000   41.37395  33.5%     -    0s
     0     0   40.67803    0  119   31.00000   40.67803  31.2%     -    0s
     0     0   40.37047    0  119   31.00000   40.37047  30.2%     -    0s
     0     0   40.03533    0  120   31.00000   40.03533  29.1%     -    0s
     0     0   39.81229    0  119   31.00000   39.81229  28.4%     -    0s
     0     0   39.77256    0  119   31.00000   39.77256  28.3%     -    0s
     0     0   39.74885    0  119   31.00000   39.74885  28.2%     -    0s
     0     0   39.70628    0  120   31.00000   39.70628  28.1%     -    0s
     0     0   39.70350    0  121   31.00000   39.70350  28.1%     -    0s
     0     0   39.70350    0  121   31.00000   39.70350  28.1%     -    0s
     0     2   39.70287    0  121   31.00000   39.70287  28.1%     -    0s
   612   242   36.29452    8  119   31.00000   36.79762  18.7%  32.4    5s
   627   252   34.13793   11  121   31.00000   36.79762  18.7%  31.6   10s
  4008   752   33.80000   22   75   31.00000   34.00000  9.68%  26.4   15s

Cutting planes:
  Clique: 4
  Zero half: 57

Explored 6268 nodes (146826 simplex iterations) in 16.91 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 3.100000000000e+01, best bound 3.100000000000e+01, gap 0.0%