019f8fd211
git-subtree-dir: users/wpcarro git-subtree-mainline:464bbcb15cgit-subtree-split:24f5a642afChange-Id: I6105b3762b79126b3488359c95978cadb3efa789
33 lines
597 B
Python
33 lines
597 B
Python
from math import floor
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def find_magic_index_brute(xs):
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for i in range(len(xs)):
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if xs[i] == i:
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return i
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return -1
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def mid(lo, hi):
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return lo + floor((hi - lo) / 2)
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def find_magic_index(xs):
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lo, hi = 0, len(xs) - 1
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return do_find_magic_index(xs, 0, len(xs) - 1)
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def do_find_magic_index(xs, lo, hi):
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pass
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xss = [
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[],
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[-1,0,2,4,5,6],
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[1,1,1,1,1,5],
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[-2,-2,-2,-2,4],
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[1,2,3,4,5],
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]
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for xs in xss:
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print(xs)
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a = find_magic_index_brute(xs)
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b = find_magic_index(xs)
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print(a, b)
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assert a == b
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print("Success!")
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