Question about the benders example

Hello, I apologize for the late reply as I checked it late.

The version of my license is v9.4.3.

According to the output log, it appears that the solution could not be successfully derived.

FICO Xpress v9.4.3, Hyper, solve started 15:51:48, Mar 11, 2025

Heap usage: 389KB (peak 389KB, 85KB system)

Minimizing MILP noname using up to 12 threads and up to 31GB memory, with these control settings:

OUTPUTLOG = 1

NLPPOSTSOLVE = 1

XSLP_DELETIONCONTROL = 0

XSLP_OBJSENSE = 1

Original problem has:

     5 rows      9 cols      36 elements     4 entities

Presolved problem has:

     4 rows      8 cols      26 elements     4 entities

Presolve finished in 0 seconds

Heap usage: 419KB (peak 427KB, 85KB system)

Coefficient range          original         solved     

 Coefficients  [min,max] : [ 1.00e+00, 5.00e+00] / [ 2.50e-01, 1.25e+00]

 RHS and bounds [min,max] : [ 1.00e+00, 5.00e+00] / [ 2.00e-01, 1.25e+00]

 Objective   [min,max] : [ 1.00e+00, 9.00e+00] / [ 1.00e+00, 9.00e+00]

Autoscaling applied standard scaling

Will try to keep branch and bound tree memory usage below 23.9GB

Starting concurrent solve with dual (1 thread)

 Concurrent-Solve,  0s

      Dual     

  objective  dual inf

 D 2.7200000  .0000000

------- optimal --------

Concurrent statistics:

      Dual: 2 simplex iterations, 0.00s

Optimal solution found

  Its     Obj Value   S  Ninf Nneg  Sum Dual Inf Time

   2     2.720000   D   0   0    .000000   0

Dual solved problem

 2 simplex iterations in 0.00 seconds at time 0

Final objective            : 2.720000000000000e+00

 Max primal violation   (abs/rel) :    0.0 /    0.0

 Max dual violation    (abs/rel) :    0.0 /    0.0

 Max complementarity viol. (abs/rel) :    0.0 /    0.0

Starting root cutting & heuristics

Deterministic mode with up to 1 additional thread

 Its Type  BestSoln  BestBound  Sols  Add  Del   Gap   GInf  Time

a      7.600000   2.720000   1         64.21%    0   0

q      2.800000   2.720000   2         2.86%    0   0

 *** Search completed ***

Uncrunching matrix

Final MIP objective          : 2.800000000000000e+00

Final MIP bound            : 2.799990000000000e+00

 Solution time / primaldual integral :   0.21s/ 98.581380%

 Number of solutions found / nodes  :     2 /     1

 Max primal violation   (abs/rel) :    0.0 /    0.0

 Max integer violation   (abs  ) :    0.0

The optimal objective is: 2.8000000000000003

The first stage variables are: [1.0, -0.0, -0.0, -0.0]

The second stage variables are: [0.0, 0.0, 0.0, 0.0, 0.6000000000000001]

The objective of the second stage is: 1.8000000000000003

FICO Xpress v9.4.3, Hyper, solve started 15:51:48, Mar 11, 2025

Heap usage: 387KB (peak 387KB, 91KB system)

Minimizing MILP noname using up to 12 threads and up to 31GB memory, with these control settings:

PRESOLVE = 0

OUTPUTLOG = 1

MIPPRESOLVE = 0

SYMMETRY = 0

NLPPOSTSOLVE = 1

XSLP_DELETIONCONTROL = 0

XSLP_OBJSENSE = 1

Original problem has:

     0 rows      5 cols      0 elements     4 entities

Coefficient range          original         solved     

 Coefficients  [min,max] : [   0.0,    0.0] / [   0.0,    0.0]

 RHS and bounds [min,max] : [ 1.00e+00, 1.00e+00] / [ 1.00e+00, 1.00e+00]

 Objective   [min,max] : [ 1.00e+00, 7.00e+00] / [ 1.00e+00, 7.00e+00]

Autoscaling applied standard scaling

Will try to keep branch and bound tree memory usage below 23.9GB

Entering Integer Callback.

Integer solution found from heuristic. Checking subproblem.

User interrupt (7) triggered.

 *** Search unfinished ***  Time:   0.00 Nodes:     0

 Solution time / primaldual integral :   0.00s/ 100.000000%

 Number of solutions found / nodes  :     0 /     0

Could not solve the problem