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https://github.com/facebook/sapling.git
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23 lines
519 B
Python
23 lines
519 B
Python
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def bisect(l, r, comp, val):
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'''Bisect algorithm with custom compare function
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Returns smallest index between l and r whose value is equal to val.
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Returns None if there are no such index.
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'''
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if r < l:
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return None
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while l < r:
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m = (l + r) / 2
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cmpresult = comp(m, val)
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if cmpresult == -1:
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l = m + 1
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elif cmpresult == 0:
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r = m
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else:
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r = m - 1
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if r < l or comp(l, val) != 0:
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return None
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return l
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