Claude Opus 5とオンラインでチャット

def merge_intervals(intervals):
    """Merge overlapping intervals.

    Args:
        intervals: iterable of (start, end) pairs with start <= end.

    Returns:
        New list of disjoint (start, end) tuples sorted by start.
        Touching intervals like (1, 2) and (2, 3) are merged.
    """
    merged = []
    for start, end in sorted(tuple(iv) for iv in intervals):
        if merged and start <= merged[-1][1]:
            prev_start, prev_end = merged[-1]
            merged[-1] = (prev_start, max(prev_end, end))
        else:
            merged.append((start, end))
    return merged


def test_overlapping_and_touching():
    assert merge_intervals([(1, 3), (2, 6), (8, 10), (15, 18)]) == [
        (1, 6), (8, 10), (15, 18)]
    assert merge_intervals([(1, 2), (2, 3)]) == [(1, 3)]


def test_unsorted_and_nested():
    assert merge_intervals([(5, 7), (1, 10), (2, 3)]) == [(1, 10)]


def test_edge_cases():
    assert merge_intervals([]) == []
    assert merge_intervals([(4, 4)]) == [(4, 4)]
    assert merge_intervals([(1, 2), (3, 4)]) == [(1, 2), (3, 4)]


if __name__ == "__main__":
    test_overlapping_and_touching()
    test_unsorted_and_nested()
    test_edge_cases()
    print("all tests passed")

A couple of notes on choices worth knowing about:

• Touching intervals merge. (1, 2) and (2, 3) become (1, 3) because the comparison is start <= prev_end. If your intervals are half-open (e.g. time slots where 2 is an exclusive end), change it to start < merged[-1][1] so they stay separate.
• Input is not mutated, and the output is a list of tuples regardless of whether you pass lists or tuples in.
• Invalid intervals aren't validated. A reversed pair like (5, 1) will produce nonsense rather than an error; add a check if the input isn't trusted.

Complexity is O(n log n) time from the sort, O(n) extra space.