Build (method = -2) #dp: 207 Step-3' Graph: 11 vertices and 63 arcs (0.00s) Step-4' Graph: 8 vertices and 57 arcs (0.00s) #V4/#V3 = 0.73 #A4/#A3 = 0.90 Ready! (0.00s) Optimize a model with 28 rows, 58 columns and 163 nonzeros Presolve removed 11 rows and 11 columns Presolve time: 0.00s Presolved: 17 rows, 47 columns, 132 nonzeros Variable types: 0 continuous, 47 integer (3 binary) Found heuristic solution: objective 95.0000000 Optimize a model with 17 rows, 47 columns and 132 nonzeros Presolved: 17 rows, 47 columns, 132 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 5.500e+01 Factor NZ : 1.530e+02 Factor Ops : 1.785e+03 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 2.34952817e+02 -1.90575106e+02 8.61e+01 1.03e-01 8.77e+00 0s 1 1.10200457e+02 -2.21577796e+01 3.15e+00 2.22e-16 1.40e+00 0s 2 7.92037630e+01 3.65510869e+01 1.71e-01 8.88e-16 4.15e-01 0s 3 7.09866086e+01 5.80077990e+01 3.98e-03 4.44e-16 1.25e-01 0s 4 6.78018443e+01 6.65047678e+01 4.09e-04 2.22e-16 1.25e-02 0s 5 6.75453366e+01 6.74388833e+01 6.02e-05 1.12e-16 1.02e-03 0s 6 6.75000070e+01 6.74999829e+01 4.74e-09 2.22e-16 2.31e-07 0s 7 6.75000000e+01 6.75000000e+01 1.07e-14 2.22e-16 2.31e-13 0s Barrier solved model in 7 iterations and 0.00 seconds Optimal objective 6.75000000e+01 Root relaxation: objective 6.750000e+01, 21 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 67.50000 0 6 95.00000 67.50000 28.9% - 0s H 0 0 68.0000000 67.50000 0.74% - 0s Explored 0 nodes (21 simplex iterations) in 0.00 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 6.800000000000e+01, best bound 6.800000000000e+01, gap 0.0% Preprocessing time: 0.01 seconds Gurobi run time: 0.00 seconds Total run time: 0.01 seconds Objective: 68 Solution: 6 x [8] 10 x [4] 5 x [13] 6 x [7, 19] 8 x [5, 15] 1 x [1, 17] 9 x [1, 9] 8 x [11, 14] 2 x [6, 17, 20] 1 x [12, 20] 5 x [2, 16] 4 x [10, 10] 2 x [3, 16, 18] 1 x [11, 16]