"""
Given a list of integers, made up of (hopefully) a small number of long runs
of consecutive integers, compute a representation of the form
((start1, end1), (start2, end2) ...). Then answer the question "was x present
in the original list?" in time O(log(# runs)).
"""
"""Represent a list of integers as a sequence of ranges:
((start_0, end_0), (start_1, end_1), ...), such that the original
integers are exactly those x such that start_i <= x < end_i for some i.
Ranges are encoded as single integers (start << 32 | end), not as tuples.
"""
=
=
= -1
continue
=
=
return
return |
return ,
"""Determine if `int_` falls into one of the ranges in `ranges`."""
=
=
# we could be immediately ahead of a tuple (start, end)
# with start < int_ <= end
, =
return True
# or we could be immediately behind a tuple (int_, end)
, =
return True
return False