Build (method = -2) #dp: 6899 Step-3' Graph: 1093 vertices and 3272 arcs (0.04s) Step-4' Graph: 704 vertices and 2494 arcs (0.05s) #V4/#V3 = 0.64 #A4/#A3 = 0.76 Ready! (0.05s) Optimize a model with 723 rows, 2495 columns and 6081 nonzeros Presolve removed 178 rows and 327 columns Presolve time: 0.04s Presolved: 545 rows, 2168 columns, 5977 nonzeros Variable types: 0 continuous, 2168 integer (433 binary) Optimize a model with 545 rows, 2168 columns and 5977 nonzeros Presolved: 545 rows, 2168 columns, 5977 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 3.931e+03 Factor NZ : 1.997e+04 (roughly 1 MByte of memory) Factor Ops : 1.114e+06 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 1.22231424e+03 -3.18780376e+04 5.90e+04 1.21e-01 9.03e+01 0s 1 3.43557098e+02 -1.77563082e+04 7.69e+03 3.76e-02 1.43e+01 0s 2 1.76545358e+02 -6.63511465e+03 1.85e+03 1.72e-15 3.70e+00 0s 3 1.05599213e+02 -1.35671919e+03 2.15e+02 4.88e-15 5.43e-01 0s 4 7.86894922e+01 -3.77000657e+02 4.19e+01 2.66e-15 1.37e-01 0s 5 5.96229098e+01 -2.10424102e+02 1.83e+01 1.67e-15 7.40e-02 0s 6 4.90475884e+01 -1.07429701e+02 1.01e+01 1.46e-15 4.13e-02 0s 7 3.96085189e+01 -2.44081091e+01 2.59e+00 1.18e-15 1.58e-02 0s 8 3.64300449e+01 1.01900081e+01 1.10e+00 1.10e-15 6.39e-03 0s 9 3.56034401e+01 2.74841071e+01 3.05e-01 5.66e-15 1.94e-03 0s 10 3.50387426e+01 3.47978448e+01 3.35e-03 2.59e-15 5.61e-05 0s 11 3.50000415e+01 3.49997951e+01 2.16e-12 1.90e-15 5.68e-08 0s 12 3.50000000e+01 3.50000000e+01 5.01e-12 1.81e-15 5.70e-14 0s Barrier solved model in 12 iterations and 0.04 seconds Optimal objective 3.50000000e+01 Root relaxation: objective 3.500000e+01, 1288 iterations, 0.05 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 35.0000000 35.00000 0.0% - 0s Explored 0 nodes (1288 simplex iterations) in 0.13 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 3.500000000000e+01, best bound 3.500000000000e+01, gap 0.0% Preprocessing time: 0.07 seconds Gurobi run time: 0.13 seconds Total run time: 0.20 seconds Objective: 35 Solution: 2 x [1, 2, 5, 6, 10, 19] 4 x [1, 6, 7, 8, 15, 18] 1 x [1, 6, 10, 19] 2 x [2, 5, 6, 7, 15] 1 x [2, 5, 6, 8] 1 x [2, 5, 6, 8, 15] 2 x [2, 6, 10, 14, 15, 17, 18] 1 x [2, 6, 19] 1 x [3, 4, 6] 2 x [5, 6, 8, 12, 13, 15, 17, 18] 2 x [5, 6, 10, 12, 19] 2 x [5, 6, 11, 12, 14, 15, 16, 17] 1 x [5, 6, 14, 16, 17, 19] 3 x [6, 7, 8, 13, 15, 18] 4 x [6, 7, 9, 10, 12, 13, 18] 2 x [6, 7, 10, 15, 16, 17, 18] 2 x [6, 12, 13, 14] 1 x [6, 14, 17] 1 x [6, 19]