Build (method = -2) #dp: 1677 Step-3' Graph: 70 vertices and 477 arcs (0.01s) Step-4' Graph: 41 vertices and 419 arcs (0.01s) #V4/#V3 = 0.59 #A4/#A3 = 0.88 Ready! (0.01s) Optimize a model with 80 rows, 420 columns and 1182 nonzeros Presolve removed 16 rows and 19 columns Presolve time: 0.01s Presolved: 64 rows, 401 columns, 1141 nonzeros Variable types: 0 continuous, 401 integer (271 binary) Found heuristic solution: objective 28.0000000 Optimize a model with 64 rows, 401 columns and 1141 nonzeros Presolved: 64 rows, 401 columns, 1141 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 6.520e+02 Factor NZ : 1.313e+03 Factor Ops : 3.569e+04 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 9.18718069e+02 -1.53108290e+03 1.62e+03 2.60e-01 1.23e+01 0s 1 2.38444302e+02 -3.99324820e+02 3.03e+02 6.66e-16 2.35e+00 0s 2 5.24899820e+01 -8.45959551e+01 2.44e+01 4.44e-16 2.75e-01 0s 3 2.64064178e+01 -9.37863259e-01 1.66e+00 4.44e-16 3.81e-02 0s 4 2.32450105e+01 9.29665073e+00 7.03e-01 2.39e-16 1.82e-02 0s 5 2.02208577e+01 1.45792692e+01 1.29e-01 2.22e-16 7.04e-03 0s 6 1.94095335e+01 1.77143952e+01 2.78e-02 2.22e-16 2.10e-03 0s 7 1.90889810e+01 1.84398164e+01 8.68e-03 2.22e-16 8.02e-04 0s 8 1.89024892e+01 1.86597517e+01 1.27e-03 2.22e-16 3.00e-04 0s 9 1.88471619e+01 1.87617498e+01 2.93e-04 1.59e-16 1.05e-04 0s 10 1.88288079e+01 1.88097124e+01 4.70e-05 2.22e-16 2.36e-05 0s 11 1.88232495e+01 1.88229529e+01 1.24e-07 3.33e-16 3.66e-07 0s 12 1.88231294e+01 1.88231291e+01 2.44e-15 2.22e-16 3.67e-10 0s 13 1.88231293e+01 1.88231293e+01 1.15e-14 3.33e-16 3.69e-16 0s Barrier solved model in 13 iterations and 0.00 seconds Optimal objective 1.88231293e+01 Root relaxation: objective 1.882313e+01, 49 iterations, 0.01 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 18.82313 0 37 28.00000 18.82313 32.8% - 0s H 0 0 22.0000000 18.82313 14.4% - 0s H 0 0 21.0000000 18.82313 10.4% - 0s H 0 0 20.0000000 18.82313 5.88% - 0s 0 0 18.82667 0 42 20.00000 18.82667 5.87% - 0s 0 0 18.85714 0 50 20.00000 18.85714 5.71% - 0s 0 0 18.85714 0 51 20.00000 18.85714 5.71% - 0s H 0 0 19.0000000 18.85714 0.75% - 0s Cutting planes: Gomory: 3 Explored 0 nodes (187 simplex iterations) in 0.08 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 1.900000000000e+01, best bound 1.900000000000e+01, gap 0.0% Preprocessing time: 0.02 seconds Gurobi run time: 0.08 seconds Total run time: 0.10 seconds Objective: 19 Solution: 1 x [1, 7, 39] 1 x [19, 38] 1 x [24, 37] 1 x [6, 9, 36] 1 x [5, 12, 35] 1 x [29, 34] 2 x [30, 33] 1 x [29, 33] 1 x [31, 32] 1 x [3, 20, 32] 1 x [9, 13, 30] 1 x [2, 26, 28] 1 x [8, 16, 28] 1 x [4, 25, 27] 1 x [11, 18, 26] 1 x [13, 15, 23] 1 x [10, 14, 22] 1 x [14, 17, 21]