sw: ampl
ampl: include Availability1.ampl
Gurobi 5.5.0: mipgap = 0.00000000000000000000000001
outlev = 1
Optimize a model with 68298 rows, 1934 columns and 28751 nonzeros
Presolve removed 1934 rows and 68298 columns
Presolve time: 0.02s
Presolve: All rows and columns removed
Iteration Objective Primal Inf. Dual Inf. Time
0 9.9948451e-01 0.000000e+00 0.000000e+00 0s
179 9.9948451e-01 0.000000e+00 0.000000e+00 0s
Solved in 179 iterations and 0.06 seconds
Optimal objective 9.994845101e-01
Gurobi 5.5.0: optimal solution; objective 0.9994845101
179 simplex iterations
以上是我的输出：没有错误，但不是最佳答案。 怎么了？我无法得到正确的答案。请帮帮我。