47c5c6ac05
Defining the insert (or "siftup") function described in the "Programming Pearls" book.
30 lines
707 B
Python
30 lines
707 B
Python
from math import floor
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class Heap(object):
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def __init__(self):
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self.xs = [None]
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self.i = 1
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def __repr__(self):
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return "[{}]".format(", ".join(str(x) for x in self.xs[1:]))
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def insert(self, x):
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if len(self.xs) == 1:
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self.xs.append(x)
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self.i += 1
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return
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self.xs.append(x)
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i = self.i
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while i != 1 and self.xs[floor(i / 2)] > self.xs[i]:
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self.xs[floor(i / 2)], self.xs[i] = self.xs[i], self.xs[floor(i / 2)]
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i = floor(i / 2)
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self.i += 1
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def root(self):
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return self.xs[1]
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xs = Heap()
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print(xs)
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for x in [12, 15, 14, 21, 1, 10]:
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xs.insert(x)
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print(xs)
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