Build (method = -2) #dp: 58619 Step-3' Graph: 752 vertices and 7266 arcs (0.45s) Step-4' Graph: 621 vertices and 7006 arcs (0.46s) #V4/#V3 = 0.83 #A4/#A3 = 0.96 Ready! (0.46s) Optimize a model with 667 rows, 7007 columns and 19781 nonzeros Presolve removed 51 rows and 56 columns Presolve time: 0.18s Presolved: 616 rows, 6951 columns, 19893 nonzeros Variable types: 0 continuous, 6951 integer (5468 binary) Found heuristic solution: objective 37.0000000 Optimize a model with 616 rows, 6951 columns and 19893 nonzeros Presolved: 616 rows, 6951 columns, 19893 nonzeros Root barrier log... Ordering time: 0.02s Barrier statistics: AA' NZ : 1.354e+04 Factor NZ : 4.753e+04 (roughly 3 MBytes of memory) Factor Ops : 4.962e+06 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 2.28648668e+03 -3.10662797e+04 3.60e+04 1.17e-01 1.64e+01 0s 1 5.64910439e+02 -9.59329146e+03 7.77e+03 7.77e-16 3.59e+00 0s 2 1.59178183e+02 -3.85506602e+03 1.29e+03 6.66e-16 7.43e-01 0s 3 6.97045561e+01 -8.81481488e+02 2.20e+02 7.77e-16 1.45e-01 0s 4 3.59813183e+01 -1.66782698e+02 4.33e+01 5.55e-16 2.88e-02 0s 5 1.90095068e+01 -7.22566162e+01 1.22e+01 5.67e-16 1.02e-02 0s 6 1.37017838e+01 -3.80350288e+01 5.54e+00 4.77e-16 5.12e-03 0s 7 1.03986854e+01 -2.25073238e+01 2.46e+00 4.37e-16 2.89e-03 0s 8 8.75098505e+00 -4.78587011e+00 1.21e+00 3.72e-16 1.14e-03 0s 9 8.03210162e+00 -5.17471523e-01 7.05e-01 3.77e-16 6.89e-04 0s 10 7.54600626e+00 2.44705753e+00 4.24e-01 2.22e-16 3.99e-04 0s 11 7.56076721e+00 2.76446810e+00 4.21e-01 3.33e-16 3.76e-04 0s 12 7.51132052e+00 4.34814862e+00 3.88e-01 2.14e-16 2.49e-04 0s 13 7.18006412e+00 6.80667573e+00 2.60e-02 3.34e-16 2.75e-05 0s 14 7.14296701e+00 7.14193556e+00 7.91e-14 3.47e-16 7.42e-08 0s 15 7.14285725e+00 7.14285622e+00 2.18e-13 2.59e-16 7.42e-11 0s 16 7.14285714e+00 7.14285714e+00 3.82e-13 4.44e-16 7.99e-17 0s Barrier solved model in 16 iterations and 0.18 seconds Optimal objective 7.14285714e+00 Root relaxation: objective 7.142857e+00, 5428 iterations, 0.24 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 7.14286 0 45 37.00000 7.14286 80.7% - 1s H 0 0 8.0000000 7.14286 10.7% - 1s Explored 0 nodes (10685 simplex iterations) in 1.56 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 8.000000000000e+00, best bound 8.000000000000e+00, gap 0.0% Preprocessing time: 0.49 seconds Gurobi run time: 1.56 seconds Total run time: 2.05 seconds Objective: 8 Solution: 1 x [10, 17, 23, 27, 28, 32, 42] 1 x [3, 27, 29, 35, 40, 43, 46] 1 x [1, 8, 19, 24, 34, 36, 39] 1 x [2, 4, 5, 14, 20, 21, 35] 1 x [7, 9, 11, 15, 22, 33, 38] 1 x [6, 9, 12, 13, 26] 1 x [7, 16, 18, 31, 37, 41, 45] 1 x [25, 30, 44]