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psf/black code formatting (#1277)

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This commit is contained in:
William Zhang
2019-10-05 01:14:13 -04:00
committed by Christian Clauss
parent 07f04a2e55
commit 9eac17a408
291 changed files with 6014 additions and 4571 deletions
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36
data_structures/binary_tree/segment_tree.py
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@ -1,10 +1,12 @@
import math
class SegmentTree:
class SegmentTree:
def __init__(self, A):
self.N = len(A)
self.st = [0] * (4 * self.N) # approximate the overall size of segment tree with array N
self.st = [0] * (
4 * self.N
) # approximate the overall size of segment tree with array N
self.build(1, 0, self.N - 1)
def left(self, idx):
@ -20,51 +22,55 @@ class SegmentTree:
mid = (l + r) // 2
self.build(self.left(idx), l, mid)
self.build(self.right(idx), mid + 1, r)
self.st[idx] = max(self.st[self.left(idx)] , self.st[self.right(idx)])
self.st[idx] = max(self.st[self.left(idx)], self.st[self.right(idx)])
def update(self, a, b, val):
return self.update_recursive(1, 0, self.N - 1, a - 1, b - 1, val)
def update_recursive(self, idx, l, r, a, b, val): # update(1, 1, N, a, b, v) for update val v to [a,b]
def update_recursive(
self, idx, l, r, a, b, val
): # update(1, 1, N, a, b, v) for update val v to [a,b]
if r < a or l > b:
return True
if l == r :
if l == r:
self.st[idx] = val
return True
mid = (l+r)//2
mid = (l + r) // 2
self.update_recursive(self.left(idx), l, mid, a, b, val)
self.update_recursive(self.right(idx), mid+1, r, a, b, val)
self.st[idx] = max(self.st[self.left(idx)] , self.st[self.right(idx)])
self.update_recursive(self.right(idx), mid + 1, r, a, b, val)
self.st[idx] = max(self.st[self.left(idx)], self.st[self.right(idx)])
return True
def query(self, a, b):
return self.query_recursive(1, 0, self.N - 1, a - 1, b - 1)
def query_recursive(self, idx, l, r, a, b): #query(1, 1, N, a, b) for query max of [a,b]
def query_recursive(
self, idx, l, r, a, b
): # query(1, 1, N, a, b) for query max of [a,b]
if r < a or l > b:
return -math.inf
if l >= a and r <= b:
return self.st[idx]
mid = (l+r)//2
mid = (l + r) // 2
q1 = self.query_recursive(self.left(idx), l, mid, a, b)
q2 = self.query_recursive(self.right(idx), mid + 1, r, a, b)
return max(q1, q2)
def showData(self):
showList = []
for i in range(1,N+1):
for i in range(1, N + 1):
showList += [self.query(i, i)]
print(showList)
if __name__ == '__main__':
A = [1,2,-4,7,3,-5,6,11,-20,9,14,15,5,2,-8]
if __name__ == "__main__":
A = [1, 2, -4, 7, 3, -5, 6, 11, -20, 9, 14, 15, 5, 2, -8]
N = 15
segt = SegmentTree(A)
print(segt.query(4, 6))
print(segt.query(7, 11))
print(segt.query(7, 12))
segt.update(1,3,111)
segt.update(1, 3, 111)
print(segt.query(1, 15))
segt.update(7,8,235)
segt.update(7, 8, 235)
segt.showData()