Build (method = -2) #dp: 445 Step-3' Graph: 34 vertices and 122 arcs (0.00s) Step-4' Graph: 6 vertices and 66 arcs (0.00s) #V4/#V3 = 0.18 #A4/#A3 = 0.54 Ready! (0.00s) Optimize a model with 26 rows, 67 columns and 195 nonzeros Presolve removed 2 rows and 2 columns Presolve time: 0.00s Presolved: 24 rows, 65 columns, 191 nonzeros Variable types: 0 continuous, 65 integer (3 binary) Found heuristic solution: objective 108.0000000 Found heuristic solution: objective 104.0000000 Optimize a model with 24 rows, 65 columns and 191 nonzeros Presolved: 24 rows, 65 columns, 191 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 6.700e+01 Factor NZ : 3.000e+02 Factor Ops : 4.900e+03 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 3.41457409e+02 -3.01595266e+02 3.68e+01 2.58e-02 1.17e+01 0s 1 7.75307832e+01 -1.31204120e+02 2.02e-01 5.55e-16 1.48e+00 0s 2 5.06480507e+01 -2.73815871e+01 1.29e-02 2.22e-16 5.33e-01 0s 3 3.85411268e+01 3.18655786e+01 2.11e-15 2.22e-16 4.48e-02 0s 4 3.67003501e+01 3.66030724e+01 2.30e-14 2.22e-16 6.53e-04 0s 5 3.66666685e+01 3.66666659e+01 1.33e-14 2.22e-16 1.69e-08 0s 6 3.66666667e+01 3.66666667e+01 2.20e-14 1.11e-16 1.72e-14 0s Barrier solved model in 6 iterations and 0.00 seconds Optimal objective 3.66666667e+01 Root relaxation: objective 3.666667e+01, 53 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 36.66667 0 4 104.00000 36.66667 64.7% - 0s H 0 0 37.0000000 36.66667 0.90% - 0s Explored 0 nodes (81 simplex iterations) in 0.00 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 3.700000000000e+01, best bound 3.700000000000e+01, gap 0.0% Preprocessing time: 0.01 seconds Gurobi run time: 0.00 seconds Total run time: 0.01 seconds Objective: 37 Solution: 5 x [3, 5, 12] 2 x [8, 14, 18] 3 x [2, 10, 19] 9 x [6, 9, 11] 1 x [4, 7] 7 x [4, 7, 15] 4 x [1, 13, 20] 1 x [2, 16, 18] 5 x [5, 17, 17]