current bounds on the number of colors: 0 -- 55 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 4591 rows, 1653 columns and 15093 nonzeros Presolve time: 0.02s Presolved: 4591 rows, 1653 columns, 15093 nonzeros Variable types: 0 continuous, 1653 integer (1653 binary) Root relaxation: objective 0.000000e+00, 129 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 (239 simplex iterations) in 0.03 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 -- 27 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 2239 rows, 883 columns and 7267 nonzeros Presolve time: 0.01s Presolved: 2239 rows, 883 columns, 7267 nonzeros Variable types: 0 continuous, 883 integer (883 binary) Root relaxation: objective 0.000000e+00, 116 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 (216 simplex iterations) in 0.01 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 -- 13 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 1063 rows, 498 columns and 3354 nonzeros Presolve time: 0.00s Presolved: 1063 rows, 498 columns, 3354 nonzeros Variable types: 0 continuous, 498 integer (498 binary) Root relaxation: objective 0.000000e+00, 121 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 (231 simplex iterations) in 0.01 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 -- 6 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 559 rows, 333 columns and 1677 nonzeros Presolve time: 0.00s Presolved: 559 rows, 333 columns, 1677 nonzeros Variable types: 0 continuous, 333 integer (333 binary) Root relaxation: objective 0.000000e+00, 117 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 0 108 - 0.00000 - - 0s 0 0 0.00000 0 104 - 0.00000 - - 0s 0 0 0.00000 0 140 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Cutting planes: Gomory: 4 Zero half: 161 Explored 0 nodes (1559 simplex iterations) in 0.07 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 -- 6 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 727 rows, 388 columns and 2236 nonzeros Presolve time: 0.00s Presolved: 727 rows, 388 columns, 2236 nonzeros Variable types: 0 continuous, 388 integer (388 binary) Root relaxation: objective 0.000000e+00, 118 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 47 - 0.00000 - - 0s H 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (541 simplex iterations) in 0.01 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