current bounds on the number of colors: 0 -- 53 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:29 2012 Optimize a model with 4135 rows, 1535 columns and 13624 nonzeros Presolve time: 0.02s Presolved: 4135 rows, 1535 columns, 13624 nonzeros Variable types: 0 continuous, 1535 integer (1535 binary) Root relaxation: objective 0.000000e+00, 138 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 0.03 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 19:36:29 2012 Optimize a model with 2094 rows, 846 columns and 6812 nonzeros Presolve time: 0.01s Presolved: 2094 rows, 846 columns, 6812 nonzeros Variable types: 0 continuous, 846 integer (846 binary) Root relaxation: objective 0.000000e+00, 110 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 (183 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 19:36:29 2012 Optimize a model with 995 rows, 475 columns and 3144 nonzeros Presolve time: 0.00s Presolved: 995 rows, 475 columns, 3144 nonzeros Variable types: 0 continuous, 475 integer (475 binary) Root relaxation: objective 0.000000e+00, 111 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 (213 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 19:36:29 2012 Optimize a model with 524 rows, 316 columns and 1572 nonzeros Presolve time: 0.00s Presolved: 524 rows, 316 columns, 1572 nonzeros Variable types: 0 continuous, 316 integer (316 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 80 - 0.00000 - - 0s 0 0 0.00000 0 80 - 0.00000 - - 0s 0 0 0.00000 0 133 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Cutting planes: Gomory: 4 Zero half: 124 Explored 0 nodes (1832 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 19:36:29 2012 Optimize a model with 681 rows, 369 columns and 2096 nonzeros Presolve time: 0.00s Presolved: 681 rows, 369 columns, 2096 nonzeros Variable types: 0 continuous, 369 integer (369 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 86 - 0.00000 - - 0s H 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (392 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