def _post_order(self, node):
"""
Utility method for computing post-order
of a binary tree using iterative algorithm.
"""
visit = []
tree, size = self.tree.tree, self.tree.size
s = Stack()
s.push(node)
last = OneDimensionalArray(int, size)
last.fill(False)
while not s.is_empty:
node = s.peek
l, r = tree[node].left, tree[node].right
cl, cr = l is None or last[l], r is None or last[r]
if cl and cr:
s.pop()
visit.append(tree[node])
last[node] = True
continue
if not cr:
s.push(r)
if not cl:
s.push(l)
return visit
def __new__(cls, *vertices):
obj = object.__new__(cls)
num_vertices = len(vertices)
obj.vertices = [vertex.name for vertex in vertices]
for vertex in vertices:
obj.__setattr__(str(vertex.name), vertex)
obj.matrix = OneDimensionalArray(OneDimensionalArray, num_vertices)
for i in range(num_vertices):
obj.matrix[i] = OneDimensionalArray(bool, num_vertices)
obj.matrix[i].fill(False)
obj.edge_weights = dict()
return obj
def __new__(cls, *vertices):
obj = object.__new__(cls)
num_vertices = len(vertices)
obj.vertices = OneDimensionalArray(AdjacencyMatrixGraphNode,
num_vertices)
for vertex in vertices:
obj.vertices[vertex.name] = vertex
obj.matrix = OneDimensionalArray(OneDimensionalArray, num_vertices)
for i in range(num_vertices):
obj.matrix[i] = OneDimensionalArray(bool, num_vertices)
obj.matrix[i].fill(False)
return obj
def __new__(cls, array):
obj = object.__new__(cls)
obj.array = OneDimensionalArray(type(array[0]), array)
obj.tree = [0] * (obj.array._size + 2)
obj.flag = [0] * (obj.array._size)
for index in range(obj.array._size):
obj.update(index, array[index])
return obj
def __new__(cls, maxsize=None, top=0, items=None, dtype=int):
if not _check_type(maxsize, int):
raise ValueError("maxsize is missing.")
if not _check_type(top, int):
raise TypeError("top is not of type int.")
if items == None:
items = OneDimensionalArray(dtype, maxsize)
if not _check_type(items, OneDimensionalArray):
raise ValueError("items is not of type, OneDimensionalArray")
if items._size > maxsize:
raise ValueError("Overflow, size of items %s is greater "
"than maxsize, %s" % (items._size, maxsize))
obj = object.__new__(cls)
obj.maxsize, obj.top, obj.items, obj.dtype = \
maxsize, top, items, items._dtype
return obj
def test_Stack():
s = Stack(maxsize=3, top=0)
s.push(1)
s.push(2)
s.push(3)
assert s.top == 3
assert str(s) == '[1, 2, 3]'
raises(ValueError, lambda: s.push(4))
assert s.pop() == 3
assert s.pop() == 2
assert s.pop() == 1
assert s.top == 0
raises(ValueError, lambda: s.pop())
raises(ValueError, lambda: Stack())
raises(TypeError, lambda: Stack(maxsize=8, top=3.5))
raises(ValueError, lambda: Stack(maxsize=5, top=0, items=[1, 2, 3]))
raises(ValueError,
lambda: Stack(maxsize=5, top=0, items=OneDimensionalArray(int, 6)))
raises(NotImplementedError,
lambda: Stack(implementation='', maxsize=5, top=0))