current bounds on the number of colors: 0 -- 4 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 12 rows, 12 columns and 32 nonzeros Presolve removed 4 rows and 4 columns Presolve time: 0.00s Presolved: 8 rows, 8 columns, 24 nonzeros Variable types: 0 continuous, 8 integer (8 binary) Root relaxation: objective 0.000000e+00, 5 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 4 - 0.00000 - - 0s Explored 0 nodes (7 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 - current bounds on the number of colors: 2 -- 4 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 16 rows, 16 columns and 48 nonzeros Presolve time: 0.00s Presolved: 16 rows, 16 columns, 48 nonzeros Variable types: 0 continuous, 16 integer (16 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 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (14 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% optimal solution found: number of colors: 3