{
  "id": "cb-01",
  "name": "merge_half_open",
  "passed": true,
  "grade_detail": "all asserts passed",
  "wall_s": 14.6,
  "usage": {
    "completion_tokens": 442,
    "prompt_tokens": 99,
    "total_tokens": 541,
    "completion_tokens_details": null,
    "prompt_tokens_details": null
  },
  "answer": "```python\ndef merge_half_open(intervals):\n    if not intervals:\n        return []\n    sorted_intervals = sorted(intervals, key=lambda x: (x[0], x[1]))\n    merged = [list(sorted_intervals[0])]\n    for start, end in sorted_intervals[1:]:\n        if start <= merged[-1][1]:\n            if end > merged[-1][1]:\n                merged[-1][1] = end\n        else:\n            merged.append([start, end])\n    return merged\n```",
  "finish_reason": "stop"
}