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author | Jesusaves <cpntb1@ymail.com> | 2020-12-09 13:32:01 -0300 |
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committer | Jesusaves <cpntb1@ymail.com> | 2020-12-09 13:32:01 -0300 |
commit | 63afe4145f410a844c647d4e3f1059f568175c1e (patch) | |
tree | 15da6a890c78d73370f44f9fd5d59badfbbe60e4 /game/python-extra/idna/intranges.py | |
download | client-init.tar.gz client-init.tar.bz2 client-init.tar.xz client-init.zip |
Initial commit, forked from Spheresinit
Diffstat (limited to 'game/python-extra/idna/intranges.py')
-rw-r--r-- | game/python-extra/idna/intranges.py | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/game/python-extra/idna/intranges.py b/game/python-extra/idna/intranges.py new file mode 100644 index 0000000..fa8a735 --- /dev/null +++ b/game/python-extra/idna/intranges.py @@ -0,0 +1,53 @@ +""" +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)). +""" + +import bisect + +def intranges_from_list(list_): + """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. + """ + + sorted_list = sorted(list_) + ranges = [] + last_write = -1 + for i in range(len(sorted_list)): + if i+1 < len(sorted_list): + if sorted_list[i] == sorted_list[i+1]-1: + continue + current_range = sorted_list[last_write+1:i+1] + ranges.append(_encode_range(current_range[0], current_range[-1] + 1)) + last_write = i + + return tuple(ranges) + +def _encode_range(start, end): + return (start << 32) | end + +def _decode_range(r): + return (r >> 32), (r & ((1 << 32) - 1)) + + +def intranges_contain(int_, ranges): + """Determine if `int_` falls into one of the ranges in `ranges`.""" + tuple_ = _encode_range(int_, 0) + pos = bisect.bisect_left(ranges, tuple_) + # we could be immediately ahead of a tuple (start, end) + # with start < int_ <= end + if pos > 0: + left, right = _decode_range(ranges[pos-1]) + if left <= int_ < right: + return True + # or we could be immediately behind a tuple (int_, end) + if pos < len(ranges): + left, _ = _decode_range(ranges[pos]) + if left == int_: + return True + return False |