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Tighten up psf/black and flake8 (#2024)

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* Tighten up psf/black and flake8

* Fix some tests

* Fix some E741

* Fix some E741

* updating DIRECTORY.md

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
This commit is contained in:
Christian Clauss
2020-05-22 08:10:11 +02:00
committed by GitHub
parent 21ed8968c0
commit 1f8a21d727
124 changed files with 583 additions and 495 deletions
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15
data_structures/binary_tree/non_recursive_segment_tree.py
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@ -1,6 +1,7 @@
"""
A non-recursive Segment Tree implementation with range query and single element update,
works virtually with any list of the same type of elements with a "commutative" combiner.
works virtually with any list of the same type of elements with a "commutative"
combiner.
Explanation:
https://www.geeksforgeeks.org/iterative-segment-tree-range-minimum-query/
@ -22,7 +23,8 @@ https://www.geeksforgeeks.org/segment-tree-efficient-implementation/
>>> st.update(4, 1)
>>> st.query(3, 4)
0
>>> st = SegmentTree([[1, 2, 3], [3, 2, 1], [1, 1, 1]], lambda a, b: [a[i] + b[i] for i in range(len(a))])
>>> st = SegmentTree([[1, 2, 3], [3, 2, 1], [1, 1, 1]], lambda a, b: [a[i] + b[i] for i
... in range(len(a))])
>>> st.query(0, 1)
[4, 4, 4]
>>> st.query(1, 2)
@ -47,7 +49,8 @@ class SegmentTree:
>>> SegmentTree(['a', 'b', 'c'], lambda a, b: '{}{}'.format(a, b)).query(0, 2)
'abc'
>>> SegmentTree([(1, 2), (2, 3), (3, 4)], lambda a, b: (a[0] + b[0], a[1] + b[1])).query(0, 2)
>>> SegmentTree([(1, 2), (2, 3), (3, 4)],
... lambda a, b: (a[0] + b[0], a[1] + b[1])).query(0, 2)
(6, 9)
"""
self.N = len(arr)
@ -78,7 +81,7 @@ class SegmentTree:
p = p // 2
self.st[p] = self.fn(self.st[p * 2], self.st[p * 2 + 1])
def query(self, l: int, r: int) -> T:
def query(self, l: int, r: int) -> T: # noqa: E741
"""
Get range query value in log(N) time
:param l: left element index
@ -95,9 +98,9 @@ class SegmentTree:
>>> st.query(2, 3)
7
"""
l, r = l + self.N, r + self.N
l, r = l + self.N, r + self.N # noqa: E741
res = None
while l <= r:
while l <= r: # noqa: E741
if l % 2 == 1:
res = self.st[l] if res is None else self.fn(res, self.st[l])
if r % 2 == 0: