current bounds on the number of colors: 0 -- 15 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:55 2012 Optimize a model with 421 rows, 163 columns and 1323 nonzeros Presolve time: 0.00s Presolved: 421 rows, 163 columns, 1323 nonzeros Variable types: 0 continuous, 163 integer (163 binary) Root relaxation: objective 0.000000e+00, 37 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 (58 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 -- 7 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:55 2012 Optimize a model with 189 rows, 103 columns and 567 nonzeros Presolve time: 0.00s Presolved: 189 rows, 103 columns, 567 nonzeros Variable types: 0 continuous, 103 integer (103 binary) Root relaxation: objective 0.000000e+00, 32 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 20 - 0.00000 - - 0s 0 0 0.00000 0 30 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Explored 0 nodes (246 simplex iterations) in 0.01 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: 3 -- 7 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:55 2012 Optimize a model with 305 rows, 133 columns and 945 nonzeros Presolve time: 0.00s Presolved: 305 rows, 133 columns, 945 nonzeros Variable types: 0 continuous, 133 integer (133 binary) Root relaxation: objective 0.000000e+00, 30 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 (107 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: 3 -- 5 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:55 2012 Optimize a model with 247 rows, 118 columns and 756 nonzeros Presolve time: 0.00s Presolved: 247 rows, 118 columns, 756 nonzeros Variable types: 0 continuous, 118 integer (118 binary) Root relaxation: objective 0.000000e+00, 31 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 (59 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: 4