30 lines
686 B
Python
30 lines
686 B
Python
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def qsort(xs):
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if xs == []: return []
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pivot = xs[0]
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left = [x for x in xs if x < pivot]
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right = [x for x in xs[1:] if x >= pivot]
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return [qsort(left)] + [pivot] + [qsort(right)]
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def sorted(tree):
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if tree == []: return []
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return sorted(tree[0]) + [tree[1]] + sorted(tree[2])
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def search(tree, x):
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return _sorted(tree, x) != []
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def insert(tree, x):
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node = _sorted(tree, x)
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if node == []:
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node.append([])
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node.append(x)
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node.append([])
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def _sorted(tree, i):
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if tree == []: return tree
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pivot = tree[1]
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if pivot == i: return tree
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elif i < pivot: return _sorted(tree[0], i)
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else: return _sorted(tree[2], i)
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