Build (method = -2) #dp: 9998 Step-3' Graph: 1417 vertices and 4244 arcs (0.07s) Step-4' Graph: 992 vertices and 3394 arcs (0.07s) #V4/#V3 = 0.70 #A4/#A3 = 0.80 Ready! (0.07s) Optimize a model with 1011 rows, 3395 columns and 8205 nonzeros Presolve removed 301 rows and 543 columns Presolve time: 0.07s Presolved: 710 rows, 2852 columns, 8074 nonzeros Variable types: 0 continuous, 2852 integer (0 binary) Optimize a model with 710 rows, 2852 columns and 8074 nonzeros Presolved: 710 rows, 2852 columns, 8074 nonzeros Root barrier log... Ordering time: 0.01s Barrier statistics: AA' NZ : 5.232e+03 Factor NZ : 3.004e+04 (roughly 2 MBytes of memory) Factor Ops : 2.176e+06 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 1.59696215e+03 -6.46381711e+04 1.50e+05 3.37e-02 1.70e+02 0s 1 4.75439730e+02 -3.94822753e+04 1.96e+04 1.27e-02 2.67e+01 0s 2 1.95242320e+02 -1.59433576e+04 4.11e+03 1.53e-14 6.37e+00 0s 3 1.02445519e+02 -3.74144512e+03 6.43e+02 1.11e-14 1.16e+00 0s 4 7.64459315e+01 -1.04446342e+03 1.11e+02 4.88e-15 2.69e-01 0s 5 6.58930440e+01 -6.98158495e+02 3.28e+01 3.22e-15 1.53e-01 0s 6 5.33485874e+01 -3.10214577e+02 1.16e+01 1.55e-15 6.85e-02 0s 7 4.83284195e+01 -2.38520795e+02 6.95e+00 1.40e-15 5.27e-02 0s 8 3.82336993e+01 -1.43020176e+02 2.26e+00 1.42e-15 3.24e-02 0s 9 3.21046061e+01 -5.11774946e+01 7.99e-01 1.35e-15 1.48e-02 0s 10 2.83816676e+01 -2.64235489e+01 5.27e-01 1.31e-15 9.71e-03 0s 11 2.62883061e+01 -3.78194838e+00 3.25e-01 1.28e-15 5.33e-03 0s 12 2.50867897e+01 7.59938361e+00 2.26e-01 1.18e-15 3.10e-03 0s 13 2.44250802e+01 1.61899524e+01 1.60e-01 1.07e-15 1.47e-03 0s 14 2.31282710e+01 2.19591500e+01 1.41e-02 8.99e-16 2.07e-04 0s 15 2.30029041e+01 2.29806838e+01 2.01e-11 8.56e-16 3.90e-06 0s 16 2.30000000e+01 2.29999958e+01 1.40e-11 8.69e-16 7.34e-10 0s 17 2.30000000e+01 2.30000000e+01 4.13e-11 8.69e-16 1.10e-15 0s Barrier solved model in 17 iterations and 0.08 seconds Optimal objective 2.30000000e+01 Root relaxation: objective 2.300000e+01, 1400 iterations, 0.10 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 23.0000000 23.00000 0.0% - 0s Explored 0 nodes (2611 simplex iterations) in 0.37 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 2.300000000000e+01, best bound 2.300000000000e+01, gap 0.0% Preprocessing time: 0.09 seconds Gurobi run time: 0.37 seconds Total run time: 0.46 seconds Objective: 23 Solution: 3 x [1, 2, 3, 6, 8, 11, 16, 19] 2 x [1, 2, 4, 11, 12, 13, 14, 16, 19] 1 x [1, 2, 6, 9, 11, 13, 16, 17, 18] 1 x [1, 2, 7, 8, 11, 14, 16, 17, 18, 19] 2 x [1, 4, 7, 9, 13, 15, 16, 18, 19] 4 x [1, 5, 6, 7, 8, 10, 13, 16] 4 x [1, 6, 7, 8, 9, 11, 13, 16, 18] 5 x [4, 5, 6, 9, 10, 11, 13, 16, 18] 1 x [5, 6, 8, 9, 11, 15, 16, 19]