current bounds on the number of colors: 0 -- 6 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 33 rows, 27 columns and 99 nonzeros Presolve time: 0.00s Presolved: 33 rows, 27 columns, 99 nonzeros Variable types: 0 continuous, 27 integer (27 binary) Root relaxation: objective 0.000000e+00, 13 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (19 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 0.000000000000e+00, best bound 0.000000000000e+00, gap 0.0% current bounds on the number of colors: 0 -- 3 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 15 rows, 15 columns and 33 nonzeros Presolve removed 15 rows and 15 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Model objective exceeds cutoff Best objective -, best bound -, gap - current bounds on the number of colors: 1 -- 3 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 24 rows, 21 columns and 66 nonzeros Presolve removed 6 rows and 6 columns Presolve time: 0.00s Presolved: 18 rows, 15 columns, 54 nonzeros Variable types: 0 continuous, 15 integer (15 binary) Root relaxation: objective 0.000000e+00, 9 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 0.00000 0 6 - 0.00000 - - 0s Explored 0 nodes (18 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Model objective exceeds cutoff Best objective -, best bound 1.000000000000e+00, gap - optimal solution found: number of colors: 3