def test_merge_heaps_2(self):
"""Test merging empty and non-empty heap"""
heap1 = fib_heap.FibonacciHeap()
heap1.insert(4)
heap1.insert(6)
heap1.insert(7)
heap2 = fib_heap.FibonacciHeap()
new_heap = heap1.merge(heap2)
assert new_heap.size == 3
assert len(list(new_heap.root_nodes)) == 3
def Dijkstra(G, s, t, INF=99999):
dists = dict()
prevs = dict()
nodes = dict()
S = fib_heap.FibonacciHeap()
for v in G.g:
if v == s:
dists[v] = 0
else:
dists[v] = INF
prevs[v] = None
node_v = fib_heap.FibonacciHeap.Node(dists[v], v)
nodes[v] = node_v
S.Insert(node_v)
v = S.extract_min().value
while True:
for u in G.g[v]:
tmp = dists[v] + G.g[v][u]
if tmp < dists[u]:
dists[u] = tmp
S.decrease_key(nodes[u], tmp)
prevs[u] = v
v = S.extract_min().value
if v == t:
break
path = []
while True:
path.append(t)
t = prevs[t]
if t == s:
return path + [s]
def __init__(self, size, initialize_with): if size != None: print "Bounded Fibonacci Heap currently unsupported!" sys.exit(1) super(priority_queue_FibHeap, self).__init__(size, initialize_with) self.l = fib_heap.FibonacciHeap() for item in initialize_with: self.add(item)
def test_insert(self):
"""Test inserting ino a non-empty Heap."""
heap = fib_heap.FibonacciHeap()
heap.insert(10)
heap.insert(5)
assert heap.min.key == 5
assert len(list(heap.root_nodes)) == 2
assert heap.size == 2
def test_extract_min(self):
"""Test extracting min value from heap."""
heap = fib_heap.FibonacciHeap()
heap.insert(10)
heap.insert(5)
heap.insert(3)
heap.insert(100)
assert heap.min.key == 3
assert heap.size == 4
min_node = heap.extract_min()
assert min_node.key == 3
assert heap.size == 3
assert heap.min.key == 5
def heap_from_slides():
"""Create Fib Heap from lecture slides."""
root_nodes = parent = node.Node(24)
sub_node = node.Node(26)
sub_node.mark = True
sub_node.parent = parent
sub_node.insert(sub_node)
n = node.Node(46)
n.parent = parent
sub_node.insert(n)
sub_node.create_child(node.Node(35))
parent.create_child(sub_node)
sub_node.degree = 1
parent.degree = 2
parent = node.Node(17)
parent.create_child(node.Node(30))
parent.degree = 1
root_nodes.insert(parent)
parent = node.Node(3)
min_node = parent
sub_node = node.Node(18)
sub_node.mark = True
sub_node.insert(sub_node)
sub_sub_node = node.Node(38)
sub_sub_node.degree = 1
sub_sub_node.create_child(node.Node(41))
sub_sub_node.parent = sub_node
sub_node.insert(sub_sub_node)
n = node.Node(52)
n.parent = sub_node
sub_node.insert(n)
n = node.Node(39)
n.mark = True
sub_node.create_child(n)
parent.create_child(sub_node)
sub_node.degree = 1
parent.degree = 2
root_nodes.insert(parent)
root_nodes.insert(node.Node(7))
root_nodes.insert(node.Node(23))
heap = fib_heap.FibonacciHeap()
heap.root_nodes = root_nodes
heap.size = 14
heap.min = min_node
return heap
def test_insert_empty(self):
"""Test inserting into an empty Heap."""
heap = fib_heap.FibonacciHeap()
heap.insert(1)
assert heap.min.key == 1
assert heap.size == 1
def test_initial_size(self):
"""Initial size should be 0."""
heap = fib_heap.FibonacciHeap()
assert heap.size == 0
def test_initial_min(self):
"""Initial min should be nil."""
heap = fib_heap.FibonacciHeap()
assert heap.min is None