Gurobi 5.6.3 (linux64) logging started Wed Oct  8 05:26:17 2014

Optimize a model with 54523 rows, 54522 columns and 163100 nonzeros
Presolve time: 1.43s
Presolved: 54523 rows, 54522 columns, 163100 nonzeros
Variable types: 0 continuous, 54522 integer (54522 binary)
Found heuristic solution: objective 21.1027566

Root relaxation: objective 1.538069e+01, 3412 iterations, 0.64 seconds

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

     0     0   15.38069    0  101   21.10276   15.38069  27.1%     -    2s
H    0     0                      15.3883023   15.38069  0.05%     -    2s
H    0     0                      15.3812701   15.38069  0.00%     -    2s

Explored 0 nodes (3412 simplex iterations) in 2.44 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 1.538127005015e+01, best bound 1.538068657795e+01, gap 0.0038%