def test_non_consecutive_adding(self):
"""Test adding vertices non-consecutively."""
# Create { }.
a_graph = UnionFind()
# Add 1 to { }, which becomes { {0}, {1} }.
# Here 0 is added implicitly.
a_graph.add(1)
self.assertEqual(a_graph.n_vertices(), 2)
self.assertEqual(a_graph.connected(0, 0), True)
self.assertEqual(a_graph.connected(0, 1), False)
self.assertEqual(a_graph.connected(1, 1), True)
def test_consecutive_adding(self):
"""Test adding vertices consecutively."""
# Create { }.
a_graph = UnionFind()
# Add 0 to { }, which becomes { {0} }.
a_graph.add(0)
self.assertEqual(a_graph.n_vertices(), 1)
self.assertEqual(a_graph.connected(0, 0), True)
self.assertEqual(a_graph.connected(0, 1), False)
self.assertEqual(a_graph.connected(1, 1), False)
# Add 0 to { {0} }, nothing changes.
a_graph.add(0)
self.assertEqual(a_graph.n_vertices(), 1)
self.assertEqual(a_graph.connected(0, 0), True)
self.assertEqual(a_graph.connected(0, 1), False)
self.assertEqual(a_graph.connected(1, 1), False)
# Add 1 to { {0} }, which becomes { {0}, {1} }.
a_graph.add(1)
self.assertEqual(a_graph.n_vertices(), 2)
self.assertEqual(a_graph.connected(0, 0), True)
self.assertEqual(a_graph.connected(0, 1), False)
self.assertEqual(a_graph.connected(1, 1), True)