Build (method = -2) #dp: 2056 Step-3' Graph: 68 vertices and 194 arcs (0.01s) Step-4' Graph: 6 vertices and 70 arcs (0.01s) #V4/#V3 = 0.09 #A4/#A3 = 0.36 Ready! (0.01s) Optimize a model with 23 rows, 71 columns and 208 nonzeros Presolve removed 2 rows and 2 columns Presolve time: 0.00s Presolved: 21 rows, 69 columns, 204 nonzeros Variable types: 0 continuous, 69 integer (0 binary) Found heuristic solution: objective 177.0000000 Found heuristic solution: objective 174.0000000 Optimize a model with 21 rows, 69 columns and 204 nonzeros Presolved: 21 rows, 69 columns, 204 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 7.200e+01 Factor NZ : 2.310e+02 Factor Ops : 3.311e+03 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 4.80344842e+02 -8.03347061e+02 3.53e+01 0.00e+00 2.10e+01 0s 1 1.28885884e+02 -2.89029442e+02 1.59e+00 3.33e-16 3.15e+00 0s 2 7.04376657e+01 1.00926705e+01 1.05e-03 4.44e-16 3.94e-01 0s 3 4.55249117e+01 3.22996205e+01 4.32e-05 2.22e-16 8.54e-02 0s 4 4.43088576e+01 4.40490878e+01 3.38e-14 1.85e-16 1.68e-03 0s 5 4.42500005e+01 4.42499968e+01 3.57e-14 1.29e-16 2.41e-08 0s 6 4.42500000e+01 4.42500000e+01 3.50e-14 1.61e-16 2.42e-14 0s Barrier solved model in 6 iterations and 0.00 seconds Optimal objective 4.42500000e+01 Root relaxation: objective 4.425000e+01, 59 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 44.25000 0 6 174.00000 44.25000 74.6% - 0s H 0 0 45.0000000 44.25000 1.67% - 0s Explored 0 nodes (86 simplex iterations) in 0.00 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 4.500000000000e+01, best bound 4.500000000000e+01, gap 0.0% Preprocessing time: 0.02 seconds Gurobi run time: 0.00 seconds Total run time: 0.02 seconds Objective: 45 Solution: 2 x [1, 4, 7, 14] 4 x [2, 3, 7, 17] 3 x [3, 9, 12, 17] 1 x [1, 3, 6, 13] 7 x [6, 11, 15, 15] 1 x [6, 6, 7, 13] 8 x [1, 5, 6, 9] 13 x [6, 13, 15, 16] 4 x [6, 8, 10, 15] 1 x [12, 14, 15] 1 x [14, 15]