Build (method = -2) #dp: 332211 Step-3' Graph: 1738 vertices and 16521 arcs (3.02s) Step-4' Graph: 1119 vertices and 15283 arcs (3.03s) #V4/#V3 = 0.64 #A4/#A3 = 0.93 Ready! (3.03s) Optimize a model with 1182 rows, 15284 columns and 43619 nonzeros Presolve removed 115 rows and 192 columns Presolve time: 0.36s Presolved: 1067 rows, 15092 columns, 43770 nonzeros Variable types: 0 continuous, 15092 integer (9441 binary) Found heuristic solution: objective 48.0000000 Optimize a model with 1067 rows, 15092 columns and 43770 nonzeros Presolve removed 3 rows and 3 columns Presolved: 1064 rows, 15089 columns, 43784 nonzeros Root barrier log... Ordering time: 0.03s Barrier statistics: AA' NZ : 2.745e+04 Factor NZ : 9.787e+04 (roughly 7 MBytes of memory) Factor Ops : 1.417e+07 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 4.95955171e+03 -8.92102186e+04 1.46e+05 2.04e-01 3.53e+01 0s 1 1.59938390e+03 -2.61254267e+04 2.43e+04 7.77e-16 6.09e+00 0s 2 5.23988466e+02 -9.81741171e+03 3.99e+03 1.11e-14 1.14e+00 0s 3 2.80734221e+02 -4.15612119e+03 4.81e+02 3.22e-15 2.33e-01 0s 4 1.84145277e+02 -1.12809530e+03 1.40e+02 1.22e-15 6.74e-02 0s 5 7.66202410e+01 -3.81622820e+02 3.49e+01 3.55e-15 2.08e-02 0s 6 4.82375431e+01 -1.56211996e+02 1.65e+01 8.88e-16 9.05e-03 0s 7 3.68812403e+01 -9.65176791e+01 9.53e+00 5.27e-16 5.61e-03 0s 8 2.77239288e+01 -4.99531227e+01 5.89e+00 4.25e-16 3.22e-03 0s 9 2.24570158e+01 -1.43668002e+01 3.40e+00 3.83e-16 1.51e-03 0s 10 2.06514660e+01 -2.80516235e+00 2.26e+00 3.60e-16 9.30e-04 0s 11 2.01493647e+01 6.32681738e+00 1.90e+00 5.55e-16 5.51e-04 0s 12 1.93522393e+01 1.52565233e+01 7.16e-01 3.33e-16 1.53e-04 0s 13 1.85103948e+01 1.74425386e+01 8.73e-02 3.39e-16 3.67e-05 0s 14 1.84005242e+01 1.83971674e+01 1.64e-13 3.75e-16 1.11e-07 0s 15 1.84000005e+01 1.83999972e+01 1.82e-13 3.34e-16 1.11e-10 0s 16 1.84000000e+01 1.84000000e+01 2.03e-12 3.10e-16 1.11e-13 0s Barrier solved model in 16 iterations and 0.33 seconds Optimal objective 1.84000000e+01 Root relaxation: objective 1.840000e+01, 11755 iterations, 0.48 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 18.40000 0 63 48.00000 18.40000 61.7% - 3s H 0 0 20.0000000 18.40000 8.00% - 3s H 0 0 19.0000000 18.40000 3.16% - 3s Explored 0 nodes (19330 simplex iterations) in 3.35 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: 3.08 seconds Gurobi run time: 3.35 seconds Total run time: 6.43 seconds Objective: 19 Solution: 1 x [4, 16, 37, 48] 1 x [5, 11, 14, 17, 41] 1 x [25, 31, 43, 48, 62] 1 x [21, 41, 49, 55, 62] 1 x [3, 26, 27, 36, 58] 1 x [9, 29, 33, 44, 56] 1 x [19, 22, 38, 60, 63] 1 x [24, 39, 50, 53, 53] 1 x [1, 10, 20, 22, 26] 1 x [18, 27, 39, 54] 1 x [7, 42, 45, 57, 59] 1 x [6, 12, 37, 40, 40] 1 x [8, 15, 30, 34, 44] 1 x [7, 14, 17, 28, 61] 1 x [13, 32, 45, 59] 1 x [2, 5, 7, 37, 50] 1 x [9, 16, 30, 31, 47] 1 x [31, 35, 47, 52, 62] 1 x [23, 46, 49, 51, 55]