current bounds on the number of colors: 0 -- 2 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:51 2012 Optimize a model with 3 rows, 3 columns and 5 nonzeros Presolve removed 3 rows and 3 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Model objective exceeds cutoff Best objective -, best bound -, gap - optimal solution found: number of colors: 2