def __new__(cls):
obj = object.__new__(cls)
obj.items = BinomialHeap()
return obj
def test_BinomialHeap():
# Corner cases
assert raises(
TypeError,
lambda: BinomialHeap(root_list=[BinomialTreeNode(1, 1), None])) is True
tree1 = BinomialTree(BinomialTreeNode(1, 1), 0)
tree2 = BinomialTree(BinomialTreeNode(2, 2), 0)
bh = BinomialHeap(root_list=[tree1, tree2])
assert raises(TypeError,
lambda: bh.merge_tree(BinomialTreeNode(2, 2), None))
assert raises(TypeError, lambda: bh.merge(None))
# Testing BinomialHeap.merge
nodes = [
BinomialTreeNode(1, 1), # 0
BinomialTreeNode(3, 3), # 1
BinomialTreeNode(9, 9), # 2
BinomialTreeNode(11, 11), # 3
BinomialTreeNode(6, 6), # 4
BinomialTreeNode(14, 14), # 5
BinomialTreeNode(2, 2), # 6
BinomialTreeNode(7, 7), # 7
BinomialTreeNode(4, 4), # 8
BinomialTreeNode(8, 8), # 9
BinomialTreeNode(12, 12), # 10
BinomialTreeNode(10, 10), # 11
BinomialTreeNode(5, 5), # 12
BinomialTreeNode(21, 21)
] # 13
nodes[2].add_children(nodes[3])
nodes[4].add_children(nodes[5])
nodes[6].add_children(nodes[9], nodes[8], nodes[7])
nodes[7].add_children(nodes[11], nodes[10])
nodes[8].add_children(nodes[12])
nodes[10].add_children(nodes[13])
tree11 = BinomialTree(nodes[0], 0)
tree12 = BinomialTree(nodes[2], 1)
tree13 = BinomialTree(nodes[6], 3)
tree21 = BinomialTree(nodes[1], 0)
heap1 = BinomialHeap(root_list=[tree11, tree12, tree13])
heap2 = BinomialHeap(root_list=[tree21])
def bfs(heap):
bfs_trav = []
for i in range(len(heap.root_list)):
layer = []
bfs_q = Queue()
bfs_q.append(heap.root_list[i].root)
while len(bfs_q) != 0:
curr_node = bfs_q.popleft()
if curr_node is not None:
layer.append(curr_node.key)
for _i in range(curr_node.children._last_pos_filled + 1):
bfs_q.append(curr_node.children[_i])
if layer != []:
bfs_trav.append(layer)
return bfs_trav
heap1.merge(heap2)
expected_bfs_trav = [[1, 3, 9, 11], [2, 8, 4, 7, 5, 10, 12, 21]]
assert bfs(heap1) == expected_bfs_trav
# Testing Binomial.find_minimum
assert heap1.find_minimum().key == 1
# Testing Binomial.delete_minimum
heap1.delete_minimum()
assert bfs(heap1) == [[3], [9, 11], [2, 8, 4, 7, 5, 10, 12, 21]]
assert raises(ValueError, lambda: heap1.decrease_key(nodes[3], 15))
heap1.decrease_key(nodes[3], 0)
assert bfs(heap1) == [[3], [0, 9], [2, 8, 4, 7, 5, 10, 12, 21]]
heap1.delete(nodes[12])
assert bfs(heap1) == [[3, 8], [0, 9, 2, 7, 4, 10, 12, 21]]
# Testing BinomialHeap.insert
heap = BinomialHeap()
assert raises(IndexError, lambda: heap.find_minimum())
heap.insert(1, 1)
heap.insert(3, 3)
heap.insert(6, 6)
heap.insert(9, 9)
heap.insert(14, 14)
heap.insert(11, 11)
heap.insert(2, 2)
heap.insert(7, 7)
assert bfs(heap) == [[1, 3, 6, 2, 9, 7, 11, 14]]
def __new__(cls, **kwargs):
raise_if_backend_is_not_python(cls,
kwargs.get('backend', Backend.PYTHON))
obj = object.__new__(cls)
obj.items = BinomialHeap()
return obj