current bounds on the number of colors: 0 -- 9 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 73 rows, 52 columns and 228 nonzeros Presolve time: 0.00s Presolved: 73 rows, 52 columns, 228 nonzeros Variable types: 0 continuous, 52 integer (52 binary) Root relaxation: objective 0.000000e+00, 18 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 (31 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 -- 4 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 41 rows, 34 columns and 114 nonzeros Presolve removed 9 rows and 9 columns Presolve time: 0.00s Presolved: 32 rows, 25 columns, 96 nonzeros Variable types: 0 continuous, 25 integer (25 binary) Root relaxation: objective 0.000000e+00, 11 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 9 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Explored 0 nodes (25 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 57 rows, 43 columns and 171 nonzeros Presolve time: 0.00s Presolved: 57 rows, 43 columns, 171 nonzeros Variable types: 0 continuous, 43 integer (43 binary) Root relaxation: objective 0.000000e+00, 19 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 8 - 0.00000 - - 0s 0 0 0.00000 0 16 - 0.00000 - - 0s Cutting planes: Clique: 5 Zero half: 8 Explored 0 nodes (54 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: 4