Gurobi 5.0.1 (linux64) logging started Fri Nov 16 04:20:30 2012 Optimize a model with 6799 rows, 2550 columns and 22698 nonzeros Presolve removed 1652 rows and 2 columns Presolve time: 0.18s Presolved: 5147 rows, 2548 columns, 18792 nonzeros Variable types: 0 continuous, 2548 integer (2548 binary) Found heuristic solution: objective 50.0000000 Root relaxation: objective 3.000000e+00, 5066 iterations, 0.79 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 3.00000 0 105 50.00000 3.00000 94.0% - 2s H 0 0 21.0000000 3.00000 85.7% - 2s H 0 0 6.0000000 3.00000 50.0% - 2s H 0 0 5.0000000 3.00000 40.0% - 2s 0 0 3.00000 0 84 5.00000 3.00000 40.0% - 3s H 0 0 4.0000000 3.00000 25.0% - 3s 0 0 3.00000 0 384 4.00000 3.00000 25.0% - 4s 0 0 3.00000 0 364 4.00000 3.00000 25.0% - 5s 0 0 3.00000 0 118 4.00000 3.00000 25.0% - 8s 0 0 infeasible 0 4.00000 3.00001 25.0% - 8s Cutting planes: Zero half: 49 Explored 0 nodes (41849 simplex iterations) in 8.91 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 4.000000000000e+00, best bound 4.000000000000e+00, gap 0.0%