Build (method = -2) #dp: 16463 Step-3' Graph: 177 vertices and 523 arcs (0.11s) Step-4' Graph: 18 vertices and 205 arcs (0.11s) #V4/#V3 = 0.10 #A4/#A3 = 0.39 Ready! (0.11s) Optimize a model with 61 rows, 206 columns and 587 nonzeros Presolve removed 4 rows and 4 columns Presolve time: 0.00s Presolved: 57 rows, 202 columns, 577 nonzeros Variable types: 0 continuous, 202 integer (135 binary) Found heuristic solution: objective 25.0000000 Found heuristic solution: objective 13.0000000 Optimize a model with 57 rows, 202 columns and 577 nonzeros Presolved: 57 rows, 202 columns, 577 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 2.220e+02 Factor NZ : 6.710e+02 Factor Ops : 1.228e+04 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 1.58495236e+02 -2.25335847e+02 3.14e+01 3.13e-02 1.88e+00 0s 1 3.13461787e+01 -5.88349148e+01 1.42e-13 2.22e-16 2.30e-01 0s 2 1.93326855e+01 7.96241823e-01 4.44e-14 1.29e-02 4.64e-02 0s 3 1.27900094e+01 1.11367407e+01 1.09e-13 2.88e-04 4.06e-03 0s 4 1.25002883e+01 1.24985022e+01 8.38e-14 2.22e-16 4.35e-06 0s Barrier performed 4 iterations in 0.00 seconds Objective cutoff exceeded Root relaxation: cutoff, 0 iterations, 0.00 seconds Explored 0 nodes (0 simplex iterations) in 0.01 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 1.300000000000e+01, best bound 1.300000000000e+01, gap 0.0% Preprocessing time: 0.12 seconds Gurobi run time: 0.01 seconds Total run time: 0.13 seconds Objective: 13 Solution: 1 x [1, 6, 26, 29] 1 x [12, 21, 41, 43] 1 x [15, 30, 34, 35] 1 x [14, 32, 33, 36] 1 x [10, 18, 31, 39] 1 x [4, 9, 16, 28] 1 x [17, 25, 27, 38] 1 x [5, 11, 21, 24] 1 x [3, 19, 23, 30] 1 x [2, 17, 22, 36] 1 x [7, 13, 16, 40] 1 x [20, 39, 42] 1 x [7, 8, 37]