Build (method = -2) #dp: 27160 Step-3' Graph: 544 vertices and 11348 arcs (0.23s) Step-4' Graph: 486 vertices and 11045 arcs (0.24s) #V4/#V3 = 0.89 #A4/#A3 = 0.97 Ready! (0.24s) Optimize a model with 540 rows, 11046 columns and 32173 nonzeros Presolve removed 5 rows and 9 columns Presolve time: 0.14s Presolved: 535 rows, 11037 columns, 32155 nonzeros Variable types: 0 continuous, 11037 integer (965 binary) Found heuristic solution: objective 155.0000000 Optimize a model with 535 rows, 11037 columns and 32155 nonzeros Presolved: 535 rows, 11037 columns, 32155 nonzeros Root barrier log... Ordering time: 0.01s Barrier statistics: AA' NZ : 1.923e+04 Factor NZ : 5.176e+04 (roughly 5 MBytes of memory) Factor Ops : 6.590e+06 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 1.05702355e+04 -3.58994859e+05 1.64e+05 6.75e-02 1.42e+02 0s 1 3.37876422e+03 -6.93010195e+04 3.19e+04 1.11e-15 2.68e+01 0s 2 9.91391889e+02 -4.02033012e+04 4.98e+03 2.84e-14 5.33e+00 0s 3 7.13517570e+02 -1.50815081e+04 1.01e+03 8.88e-15 1.28e+00 0s 4 5.79984896e+02 -8.54246672e+03 4.88e+02 1.69e-14 6.47e-01 0s 5 4.96426953e+02 -5.99471501e+03 2.88e+02 1.51e-14 4.17e-01 0s 6 4.81511874e+02 -4.96984401e+03 2.60e+02 1.02e-14 3.51e-01 0s 7 4.22086963e+02 -2.70922776e+03 1.59e+02 1.64e-14 1.94e-01 0s 8 3.43607320e+02 -1.85436878e+03 7.53e+01 1.02e-14 1.20e-01 0s 9 2.77984814e+02 -7.94593550e+02 3.31e+01 4.44e-15 5.50e-02 0s 10 2.24999353e+02 -4.60957216e+02 1.73e+01 2.33e-15 3.39e-02 0s 11 1.96609814e+02 -3.45659512e+02 1.26e+01 1.89e-15 2.64e-02 0s 12 1.79100937e+02 -3.21875090e+02 9.71e+00 2.00e-15 2.40e-02 0s 13 1.32691364e+02 -2.99864758e+02 7.93e+00 1.89e-15 2.07e-02 0s 14 9.63751994e+01 -1.50443641e+02 5.37e+00 9.99e-16 1.18e-02 0s 15 7.86390631e+01 -1.09292604e+02 4.23e+00 5.55e-16 9.00e-03 0s 16 5.34002556e+01 -6.78762876e+01 2.69e+00 4.13e-16 5.78e-03 0s 17 4.62931415e+01 -5.79509587e+01 2.13e+00 5.00e-16 4.94e-03 0s 18 3.88126180e+01 -3.06633544e+01 1.37e+00 4.64e-16 3.26e-03 0s 19 3.63210844e+01 -1.06278389e+01 8.85e-01 3.99e-16 2.18e-03 0s 20 3.34870010e+01 8.50954504e+00 5.68e-01 4.29e-16 1.15e-03 0s 21 3.05130554e+01 1.94321788e+01 2.09e-01 2.90e-16 5.07e-04 0s 22 2.94820666e+01 2.34363679e+01 1.13e-01 3.63e-16 2.76e-04 0s 23 2.91156377e+01 2.58983169e+01 8.32e-02 3.36e-16 1.47e-04 0s 24 2.84692862e+01 2.69677305e+01 3.62e-02 3.68e-16 6.85e-05 0s 25 2.80130589e+01 2.74790238e+01 3.31e-03 3.25e-16 2.42e-05 0s 26 2.79762876e+01 2.77111606e+01 1.44e-03 3.94e-16 1.20e-05 0s 27 2.79541548e+01 2.78929079e+01 3.25e-04 3.86e-16 2.77e-06 0s 28 2.79470739e+01 2.79121157e+01 3.41e-05 3.77e-16 1.58e-06 0s 29 2.79469905e+01 2.79197288e+01 3.17e-05 4.08e-16 1.23e-06 0s 30 2.79460012e+01 2.79459734e+01 9.33e-13 4.44e-16 1.26e-09 0s 31 2.79460000e+01 2.79460000e+01 1.35e-13 3.58e-16 1.26e-12 0s Barrier solved model in 31 iterations and 0.35 seconds Optimal objective 2.79460000e+01 Root relaxation: objective 2.794600e+01, 6432 iterations, 0.54 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 27.94600 0 118 155.00000 27.94600 82.0% - 2s H 0 0 30.0000000 27.94600 6.85% - 2s H 0 0 29.0000000 27.94600 3.63% - 3s 0 0 27.94600 0 111 29.00000 27.94600 3.63% - 6s 0 0 27.94600 0 125 29.00000 27.94600 3.63% - 9s H 0 0 28.0000000 27.94600 0.19% - 9s Explored 0 nodes (41602 simplex iterations) in 9.59 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 2.800000000000e+01, best bound 2.800000000000e+01, gap 0.0% Preprocessing time: 0.29 seconds Gurobi run time: 9.59 seconds Total run time: 9.89 seconds Objective: 28 Solution: 2 x [5, 5, 13, 13, 37, 40, 50] 1 x [3, 7, 15, 23, 32, 40, 43] 1 x [4, 11, 12, 15, 32, 40, 49] 1 x [4, 4, 4, 19, 19, 20, 40] 1 x [4, 6, 34, 37, 39, 41, 54] 1 x [2, 9, 28, 36, 39, 49, 54] 2 x [2, 7, 8, 31, 35, 39, 41] 1 x [25, 34, 37, 38, 43, 44, 47] 1 x [16, 19, 23, 23, 38, 49, 50] 1 x [1, 10, 12, 29, 30, 36, 46] 1 x [1, 10, 10, 18, 20, 36, 44] 1 x [3, 9, 19, 24, 30, 35, 44] 1 x [5, 5, 17, 24, 28, 35, 50] 2 x [9, 19, 22, 33, 33, 48, 53] 1 x [5, 8, 9, 30, 31, 32, 49] 1 x [10, 18, 31, 32, 32, 46, 48] 1 x [4, 5, 18, 20, 26, 30, 44] 1 x [1, 14, 18, 23, 25, 30, 46] 1 x [3, 9, 25, 26, 29, 29, 44] 1 x [1, 5, 11, 11, 25, 29, 29] 2 x [6, 27, 42, 43, 43, 45, 49, 53] 1 x [12, 14, 16, 16, 16, 16, 21] 1 x [1, 20, 43, 44, 48, 49, 51, 52] 1 x [6, 7, 7, 41, 46, 46, 47, 54]