Build (method = -2) #dp: 8797 Step-3' Graph: 110 vertices and 320 arcs (0.04s) Step-4' Graph: 16 vertices and 132 arcs (0.04s) #V4/#V3 = 0.15 #A4/#A3 = 0.41 Ready! (0.04s) Optimize a model with 36 rows, 133 columns and 374 nonzeros Presolve removed 6 rows and 10 columns Presolve time: 0.00s Presolved: 30 rows, 123 columns, 356 nonzeros Variable types: 0 continuous, 123 integer (0 binary) Found heuristic solution: objective 104.0000000 Optimize a model with 30 rows, 123 columns and 356 nonzeros Presolved: 30 rows, 123 columns, 356 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 1.330e+02 Factor NZ : 3.430e+02 Factor Ops : 5.215e+03 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 7.19837211e+02 -1.38104573e+03 1.99e+02 1.11e-16 2.42e+01 0s 1 1.78814870e+02 -5.76847967e+02 6.68e+00 4.44e-16 3.34e+00 0s 2 8.68563733e+01 -2.77454842e+01 2.56e-02 7.22e-16 4.37e-01 0s 3 4.21681877e+01 2.64871341e+01 9.49e-04 4.44e-16 5.90e-02 0s 4 4.02517887e+01 3.95555163e+01 9.05e-05 3.33e-16 2.62e-03 0s 5 4.00001714e+01 3.99986503e+01 2.07e-14 3.33e-16 5.72e-06 0s 6 4.00000000e+01 4.00000000e+01 1.79e-14 4.44e-16 5.77e-12 0s Barrier solved model in 6 iterations and 0.00 seconds Optimal objective 4.00000000e+01 Root relaxation: objective 4.000000e+01, 105 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 40.0000000 40.00000 0.0% - 0s Explored 0 nodes (105 simplex iterations) in 0.00 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 4.000000000000e+01, best bound 4.000000000000e+01, gap 0.0% Preprocessing time: 0.05 seconds Gurobi run time: 0.00 seconds Total run time: 0.05 seconds Objective: 40 Solution: 2 x [1, 2, 7, 10, 13] 13 x [1, 10, 18, 19, 20] 5 x [2, 2, 4, 17, 18] 2 x [1, 4, 8, 9, 16] 4 x [2, 3, 9, 11, 17] 1 x [2, 2, 2, 13, 17] 6 x [5, 11, 14, 16, 17] 5 x [5, 6, 7, 15, 20] 1 x [7, 8, 12, 13, 20] 1 x [5, 8, 9, 11, 12]