Build (method = -2) #dp: 2919 Step-3' Graph: 80 vertices and 230 arcs (0.01s) Step-4' Graph: 8 vertices and 86 arcs (0.01s) #V4/#V3 = 0.10 #A4/#A3 = 0.37 Ready! (0.01s) Optimize a model with 27 rows, 87 columns and 252 nonzeros Presolve removed 2 rows and 2 columns Presolve time: 0.00s Presolved: 25 rows, 85 columns, 248 nonzeros Variable types: 0 continuous, 85 integer (8 binary) Found heuristic solution: objective 197.0000000 Found heuristic solution: objective 181.0000000 Optimize a model with 25 rows, 85 columns and 248 nonzeros Presolved: 25 rows, 85 columns, 248 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 9.000e+01 Factor NZ : 3.250e+02 Factor Ops : 5.525e+03 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 8.18805847e+02 -8.99561974e+02 1.63e+02 3.91e-02 3.07e+01 0s 1 1.71164779e+02 -4.50003239e+02 6.36e+00 7.66e-15 4.07e+00 0s 2 8.89332663e+01 -1.07507684e+01 1.28e-02 1.11e-14 5.40e-01 0s 3 5.19423745e+01 3.39801414e+01 2.55e-04 9.14e-15 9.61e-02 0s 4 5.01704400e+01 4.90280894e+01 1.93e-05 7.44e-15 6.11e-03 0s 5 5.00001226e+01 4.99990107e+01 3.93e-10 9.20e-15 5.95e-06 0s 6 5.00000000e+01 5.00000000e+01 6.56e-14 1.08e-14 5.99e-12 0s Barrier solved model in 6 iterations and 0.00 seconds Optimal objective 5.00000000e+01 Root relaxation: objective 5.000000e+01, 73 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 50.0000000 50.00000 0.0% - 0s Explored 0 nodes (73 simplex iterations) in 0.00 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 5.000000000000e+01, best bound 5.000000000000e+01, gap 0.0% Preprocessing time: 0.02 seconds Gurobi run time: 0.00 seconds Total run time: 0.02 seconds Objective: 50 Solution: 15 x [4, 16, 17, 19] 2 x [4, 7, 11, 13] 4 x [2, 3, 12, 13] 3 x [3, 5, 13, 18] 10 x [5, 10, 11, 18] 1 x [1, 11, 14, 15] 2 x [2, 13, 13, 16] 7 x [1, 7, 7, 16] 4 x [9, 13, 14, 16] 1 x [7, 8, 13, 17] 1 x [6, 8, 11, 17]