Iteration final - SOLVER_EXECUTION
Sequence: 6
Timestamp: 2025-07-25 22:27:59

Prompt:
Generated solver codes with templates and executed them with retry logic

Response:
{
  "gurobipy": {
    "solver_type": "gurobipy",
    "execution_time": 0.2860724925994873,
    "return_code": 1,
    "stdout": "Restricted license - for non-production use only - expires 2026-11-23\n",
    "stderr": "Traceback (most recent call last):\n  File \"/tmp/tmpsd66dh82.py\", line 69, in <module>\n    optimize_student_friendship()\n  File \"/tmp/tmpsd66dh82.py\", line 50, in optimize_student_friendship\n    model.addConstr(x[i, j] == x[j, i], name=f\"mutual_{i}_{j}\")\nKeyError: (3, 2)\n",
    "status": "error",
    "optimal_value": null,
    "error_message": "Traceback (most recent call last):\n  File \"/tmp/tmpsd66dh82.py\", line 69, in <module>\n    optimize_student_friendship()\n  File \"/tmp/tmpsd66dh82.py\", line 50, in optimize_student_friendship\n    model.addConstr(x[i, j] == x[j, i], name=f\"mutual_{i}_{j}\")\nKeyError: (3, 2)\n",
    "decision_variables": {}
  },
  "docplex": {
    "solver_type": "docplex",
    "execution_time": 1.8511922359466553,
    "return_code": 0,
    "stdout": "Optimal value: 3.0\nFriendship between 1 and 2 is established.\nFriendship between 1 and 3 is established.\nFriendship between 2 and 1 is established.\nFriendship between 2 and 3 is established.\nFriendship between 3 and 1 is established.\nFriendship between 3 and 2 is established.\n",
    "stderr": "",
    "status": "optimal",
    "optimal_value": 3.0,
    "error_message": null,
    "decision_variables": {}
  },
  "pyomo": {
    "solver_type": "pyomo",
    "execution_time": 1.0493242740631104,
    "return_code": 0,
    "stdout": "Read LP format model from file /tmp/tmp_d3sgosn.pyomo.lp\nReading time = 0.00 seconds\nx1: 15 rows, 10 columns, 30 nonzeros\nSet parameter TimeLimit to value 300\nSet parameter MIPGap to value 0.01\nGurobi Optimizer version 12.0.2 build v12.0.2rc0 (linux64 - \"Red Hat Enterprise Linux 9.4 (Plow)\")\n\nCPU model: AMD EPYC 7513 32-Core Processor, instruction set [SSE2|AVX|AVX2]\nThread count: 64 physical cores, 128 logical processors, using up to 32 threads\n\nNon-default parameters:\nTimeLimit  300\nMIPGap  0.01\n\nOptimize a model with 15 rows, 10 columns and 30 nonzeros\nModel fingerprint: 0xa2df2b92\nVariable types: 1 continuous, 9 integer (9 binary)\nCoefficient statistics:\n  Matrix range     [1e+00, 1e+00]\n  Objective range  [1e+00, 1e+00]\n  Bounds range     [1e+00, 1e+00]\n  RHS range        [2e+00, 5e+00]\nFound heuristic solution: objective 3.0000000\n\nExplored 0 nodes (0 simplex iterations) in 0.00 seconds (0.00 work units)\nThread count was 1 (of 128 available processors)\n\nSolution count 1: 3 \n\nOptimal solution found (tolerance 1.00e-02)\nBest objective 3.000000000000e+00, best bound 3.000000000000e+00, gap 0.0000%\nOptimal solution found!\nOptimal value: 3.0\n\nFriendship pairings:\nStudent 1 is friends with Student 2\nStudent 1 is friends with Student 3\nStudent 2 is friends with Student 3\n",
    "stderr": "",
    "status": "optimal",
    "optimal_value": 3.0,
    "error_message": null,
    "decision_variables": {}
  }
}
