current bounds on the number of colors: 0 -- 52 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:27 2012 Optimize a model with 3978 rows, 1503 columns and 13130 nonzeros Presolve time: 0.02s Presolved: 3978 rows, 1503 columns, 13130 nonzeros Variable types: 0 continuous, 1503 integer (1503 binary) Root relaxation: objective 0.000000e+00, 128 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 (217 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 -- 26 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:27 2012 Optimize a model with 2015 rows, 827 columns and 6565 nonzeros Presolve time: 0.01s Presolved: 2015 rows, 827 columns, 6565 nonzeros Variable types: 0 continuous, 827 integer (827 binary) Root relaxation: objective 0.000000e+00, 109 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 (198 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 19:36:27 2012 Optimize a model with 958 rows, 463 columns and 3030 nonzeros Presolve time: 0.00s Presolved: 958 rows, 463 columns, 3030 nonzeros Variable types: 0 continuous, 463 integer (463 binary) Root relaxation: objective 0.000000e+00, 113 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 (272 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 19:36:27 2012 Optimize a model with 505 rows, 307 columns and 1515 nonzeros Presolve time: 0.00s Presolved: 505 rows, 307 columns, 1515 nonzeros Variable types: 0 continuous, 307 integer (307 binary) Root relaxation: objective 0.000000e+00, 119 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 96 - 0.00000 - - 0s 0 0 0.00000 0 109 - 0.00000 - - 0s 0 0 0.00000 0 129 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Cutting planes: Gomory: 9 Clique: 1 Zero half: 73 Explored 0 nodes (1613 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 19:36:27 2012 Optimize a model with 656 rows, 359 columns and 2020 nonzeros Presolve time: 0.00s Presolved: 656 rows, 359 columns, 2020 nonzeros Variable types: 0 continuous, 359 integer (359 binary) Root relaxation: objective 0.000000e+00, 122 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 28 - 0.00000 - - 0s H 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (772 simplex iterations) in 0.02 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