Gurobi 5.6.3 (linux64) logging started Wed Oct 8 04:41:21 2014 Optimize a model with 51303 rows, 51302 columns and 153454 nonzeros Presolve time: 1.32s Presolved: 51303 rows, 51302 columns, 153454 nonzeros Variable types: 0 continuous, 51302 integer (51302 binary) Found heuristic solution: objective 24.1216072 Root relaxation: objective 1.516289e+01, 2902 iterations, 0.48 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 15.16289 0 66 24.12161 15.16289 37.1% - 1s H 0 0 16.1858240 15.16289 6.32% - 2s H 0 0 15.1647096 15.16289 0.01% - 2s Explored 0 nodes (2902 simplex iterations) in 2.91 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 1.516470960456e+01, best bound 1.516470960456e+01, gap 0.0%