Build (method = -2) #dp: 7300 Step-3' Graph: 295 vertices and 876 arcs (0.07s) Step-4' Graph: 90 vertices and 466 arcs (0.07s) #V4/#V3 = 0.31 #A4/#A3 = 0.53 Ready! (0.07s) Optimize a model with 132 rows, 467 columns and 1227 nonzeros Presolve removed 23 rows and 45 columns Presolve time: 0.01s Presolved: 109 rows, 422 columns, 1139 nonzeros Variable types: 0 continuous, 422 integer (55 binary) Found heuristic solution: objective 86.0000000 Found heuristic solution: objective 60.0000000 Optimize a model with 109 rows, 422 columns and 1139 nonzeros Presolved: 109 rows, 422 columns, 1139 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 5.240e+02 Factor NZ : 9.640e+02 Factor Ops : 1.055e+04 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 5.31613908e+02 -1.09920585e+03 5.68e+02 1.07e-01 7.44e+00 0s 1 1.31717119e+02 -5.27387285e+02 4.31e+01 4.44e-16 1.11e+00 0s 2 5.69630221e+01 -8.19055738e+01 4.43e-01 3.33e-16 1.61e-01 0s 3 2.45716247e+01 -5.67967577e+00 2.92e-02 1.73e-16 3.47e-02 0s 4 2.06342465e+01 1.81391517e+01 1.08e-04 3.33e-16 2.85e-03 0s 5 2.00057380e+01 1.99943625e+01 2.48e-07 1.75e-16 1.30e-05 0s 6 2.00000000e+01 2.00000000e+01 3.38e-13 2.64e-16 1.58e-11 0s Barrier solved model in 6 iterations and 0.00 seconds Optimal objective 2.00000000e+01 Root relaxation: objective 2.000000e+01, 282 iterations, 0.01 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 20.00000 0 4 60.00000 20.00000 66.7% - 0s H 0 0 21.0000000 20.00000 4.76% - 0s H 0 0 20.0000000 20.00000 0.0% - 0s Explored 0 nodes (343 simplex iterations) in 0.02 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 2.000000000000e+01, best bound 2.000000000000e+01, gap 0.0% Preprocessing time: 0.08 seconds Gurobi run time: 0.02 seconds Total run time: 0.11 seconds Objective: 20 Solution: 2 x [3, 14, 21, 39, 42] 1 x [3, 4, 13, 25, 41] 1 x [6, 7, 13, 17, 41] 3 x [8, 27, 38, 39, 40] 1 x [20, 25, 32, 36, 40] 1 x [13, 22, 23, 28, 37] 3 x [2, 24, 26, 27, 36] 3 x [1, 5, 9, 31, 35] 2 x [11, 16, 19, 29, 34] 2 x [10, 15, 16, 18, 33] 1 x [9, 12, 13, 20, 30]