def test_is_graph_cyclic(setup_graph):
gr = setup_graph
assert is_graph_cyclic(gr) == True
gr = graph()
gr.add_nodes(["0", "1", "2", "3"])
gr.add_edges([("0", "1"), ("1", "2"), ("2", "3")])
assert is_graph_cyclic(gr) == False
def setup_graph():
gr = graph()
gr.add_nodes(["s", "a", "b", "c", "d", "e", "f", "g", "h", "j", "k", "l"])
gr.add_edges([("s", "a"), ("s", "b"), ("a", "c"), ("c", "e")])
gr.add_edges([("e", "d"), ("d", "b"), ("a", "b"), ("c", "d")])
gr.add_edges([("g", "h"), ("f", "g")])
gr.add_edges([("j", "k"), ("j", "l")])
return gr
def setUp(self):
self.gr = graph()
self.gr.add_nodes(["a", "b", "c", "d", "e", "f"])
self.gr.add_edge(("a", "b"))
self.gr.add_edge(("a", "f"))
self.gr.add_edge(("b", "c"))
self.gr.add_edge(("c", "e"))
self.gr.add_edge(("c", "d"))
self.gr.add_edge(("d", "f"))
def test_kruskals_minimum_spanning_tree(self):
gr = graph()
gr.add_nodes(["a", "b", "c", "d"])
gr.add_edge(("a", "b"), 4)
gr.add_edge(("b", "c"), 3)
gr.add_edge(("a", "c"), 1)
gr.add_edge(("c", "d"), 2)
min_cost = kruskal_MST(gr)
self.assertEqual(min_cost, 6)
def test_kruskals_minimum_spanning_tree(setup_graph):
gr = setup_graph
gr = graph()
gr.add_nodes(["a", "b", "c", "d"])
gr.add_edge(("a", "b"), 4)
gr.add_edge(("b", "c"), 3)
gr.add_edge(("a", "c"), 1)
gr.add_edge(("c", "d"), 2)
min_cost = kruskal_MST(gr)
assert min_cost == 6
def setup_graph():
gr = graph()
gr.add_nodes(["a", "b", "c", "d", "e", "f"])
gr.add_edge(("a", "b"))
gr.add_edge(("a", "f"))
gr.add_edge(("b", "c"))
gr.add_edge(("c", "e"))
gr.add_edge(("c", "d"))
gr.add_edge(("d", "f"))
return gr
def test_kruskals_minimum_spanning_tree(self):
lines = [l for l in open("tests/edges.txt")]
lines = lines[1:]
edges = (l.split() for l in lines)
gr = graph()
for (u, v, w) in edges:
if u not in gr.nodes():
gr.add_node(u)
if v not in gr.nodes():
gr.add_node(v)
gr.add_edge((u, v), int(w))
min_cost = kruskal_MST(gr)
self.assertEqual(min_cost, 39)
def setUp(self):
self.gr = graph()
self.gr.add_nodes(["s", "a", "b", "c", "d", "e", "f", "g", "h", "j", "k", "l"])
self.gr.add_edges([("s", "a"), ("s", "b"), ("a", "c"), ("c", "e")])
self.gr.add_edges([("e", "d"), ("d", "b"), ("a", "b"), ("c", "d")])
self.gr.add_edges([("g", "h"), ("f", "g")])
self.gr.add_edges([("j", "k"), ("j", "l")])
self.digr = digraph()
self.digr.add_nodes(["s", "a", "b", "c", "d", "e", "f"])
self.digr.add_edges([("s", "a"), ("a", "b"), ("b", "a"), ("c", "b")])
self.digr.add_edges([("b", "s"), ("s", "d"), ("d", "e"), ("e", "d")])
self.digr.add_edges([("b", "f"), ("e", "f")])
def setUp(self):
self.gr = graph()
self.gr.add_nodes(["s", "a", "b", "c", "d", "e", "f", "g", "h", "j", "k", "l"])
self.gr.add_edges([("s", "a"), ("s", "b"), ("a", "c"), ("c", "e")])
self.gr.add_edges([("e", "d"), ("d", "b"), ("a", "b"), ("c", "d")])
self.gr.add_edges([("g", "h"), ("f", "g")])
self.gr.add_edges([("j", "k"), ("j", "l")])
self.digr = digraph()
self.digr.add_nodes(['s', 'a', 'b', 'c', 'd', 'e', 'f'])
self.digr.add_edges([("s", "a"), ("a", "b"), ("b", "a"), ("c", "b")])
self.digr.add_edges([("b", "s"), ("s", "d"), ("d", "e"), ("e", "d")])
self.digr.add_edges([("b", "f"), ("e", "f")])
def test_kruskals_minimum_spanning_tree(self):
lines = [l for l in open("tests/edges.txt")]
lines = lines[1:]
edges = (l.split() for l in lines)
gr = graph()
for (u, v, w) in edges:
if u not in gr.nodes():
gr.add_node(u)
if v not in gr.nodes():
gr.add_node(v)
gr.add_edge((u, v), int(w))
min_cost = kruskal_MST(gr)
self.assertEqual(min_cost, 39)
import os, sys
sys.path.append(os.path.join(os.getcwd(), os.path.pardir))
from graphs.graph import graph
from union_find.unionfind import UnionFind
lines = [l for l in open("edges.txt").readlines()]
lines = lines[1:]
edges = [l.split() for l in lines]
gr = graph()
for (u, v, w) in edges:
if u not in gr.nodes():
gr.add_node(u)
if v not in gr.nodes():
gr.add_node(v)
gr.add_edge((u, v), int(w))
def kruskal_MST(gr):
sorted_edges = sorted(gr.get_edge_weights())
uf = UnionFind()
min_cost = 0
for (w, (u, v)) in sorted_edges:
if (not uf.get_leader(u) and not uf.get_leader(v)) or (uf.get_leader(u) != uf.get_leader(v)):
uf.insert(u, v)
min_cost += w
return min_cost
print kruskal_MST(gr)
