34 lines
1015 B
Python
34 lines
1015 B
Python
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def Ordered_binary_Search(olist, item):
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if len(olist) == 0:
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return False
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else:
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midpoint = len(olist) // 2
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if olist[midpoint] == item:
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return True
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else:
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if item < olist[midpoint]:
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return binarySearch(olist[:midpoint], item)
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else:
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return binarySearch(olist[midpoint+1:], item)
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def binarySearch(alist, item):
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first = 0
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last = len(alist) - 1
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found = False
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while first <= last and not found:
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midpoint = (first + last) // 2
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if alist[midpoint] == item:
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found = True
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else:
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if item < alist[midpoint]:
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last = midpoint - 1
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else:
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first = midpoint + 1
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return found
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print(Ordered_binary_Search([0, 1, 3, 8, 14, 18, 19, 34, 52], 3))
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print(Ordered_binary_Search([0, 1, 3, 8, 14, 18, 19, 34, 52], 17))
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