bisect

二分探索 「kを超える最初の場所」がright、「k以上の最初の場所」がleft python

>>> import bisect
>>> xs = [1, 2, 4, 4, 5]
>>> [bisect.bisect_left(xs, x) for x in range(7)]
[0, 0, 1, 2, 2, 4, 5]
>>> [bisect.bisect_right(xs, x) for x in range(7)]
[0, 1, 2, 2, 4, 5, 5]

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