def test_cut__leaves_bothTreesIntact(self):
# arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
a4 = tree.makeTree('a4')
a5 = tree.makeTree('a5')
a6 = tree.makeTree('a6')
tree.link(a1, a2)
tree.link(a2, a3)
tree.link(a3, a4)
tree.link(a4, a5)
tree.link(a5, a6)
c1 = tree.makeTree('c1')
c2 = tree.makeTree('c2')
c3 = tree.makeTree('c3')
tree.link(c1, c2)
tree.link(c2, c3)
tree.link(a6, c1)
#act
tree.cut(c2)
#assert
self.assertEqual(a1, tree.getRoot(c1))
self.assertEqual(c2, tree.getRoot(c3))
def test_lca_multipleLinks_shouldFindLCA(self):
tree = LinkCutTree()
#Arrange
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
a4 = tree.makeTree('a4')
a5 = tree.makeTree('a5')
a6 = tree.makeTree('a6')
tree.link(a1, a2)
tree.link(a2, a3)
tree.link(a3, a4)
tree.link(a4, a5)
tree.link(a5, a6)
b1 = tree.makeTree('b1')
b2 = tree.makeTree('b2')
b3 = tree.makeTree('b3')
tree.link(b1, b2)
tree.link(b2, b3)
tree.link(a3, b1)
c1 = tree.makeTree('c1')
c2 = tree.makeTree('c2')
c3 = tree.makeTree('c3')
tree.link(c1, c2)
tree.link(c1, c3)
tree.link(a5, c1)
self.assertEqual(tree.lca(c3, b3), a3)
def test_makeRoot_path_shouldFlipPath(self):
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
a4 = tree.makeTree('a4')
a5 = tree.makeTree('a5')
a6 = tree.makeTree('a6')
tree.link(a1, a2, 1)
tree.link(a2, a3, 2)
tree.link(a3, a4, 3)
tree.link(a4, a5, 4)
tree.link(a5, a6, 5)
#act
tree.makeRoot(a6)
#assert
self.assertEqual(a6, tree.getRoot(a1))
self.assertEqual(a6, a5.represented_parent)
self.assertEqual(a5, a4.represented_parent)
self.assertEqual(a4, a3.represented_parent)
self.assertEqual(a3, a2.represented_parent)
self.assertEqual(a2, a1.represented_parent)
def test_link_threeTrees_getRootShouldBeSameForAll(self):
tree = LinkCutTree()
#Arrange
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
a4 = tree.makeTree('a4')
a5 = tree.makeTree('a5')
a6 = tree.makeTree('a6')
tree.link(a1, a2)
tree.link(a2, a3)
tree.link(a3, a4)
tree.link(a4, a5)
tree.link(a5, a6)
b1 = tree.makeTree('b1')
b2 = tree.makeTree('b2')
b3 = tree.makeTree('b3')
tree.link(b1, b2)
tree.link(b2, b3)
tree.link(a3, b1)
c1 = tree.makeTree('c1')
c2 = tree.makeTree('c2')
c3 = tree.makeTree('c3')
tree.link(c1, c2)
tree.link(c2, c3)
tree.link(a5, c1)
# act/assert
self.assertEqual(a1, tree.getRoot(c1))
self.assertEqual(a1, tree.getRoot(b3))
def test_lca_query_order_doesnt_matter(self):
#Arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
tree.link(a1, a2)
tree.link(a2, a3)
self.assertEqual(tree.lca(a2, a3), tree.lca(a3, a2))
def test_lca_path_shouldReturnOlderNode(self):
#Arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
tree.link(a1, a2)
tree.link(a2, a3)
self.assertEqual(tree.lca(a2, a3), a2)
def test_lca_balancedTree_ShouldReturnRoot(self):
#Arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
tree.link(a1, a2)
tree.link(a1, a3)
self.assertEqual(tree.lca(a2, a3), a1)
def test_getRoot__returnsProperRootWhenRootHasMultipleChildren(self):
#arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
b1 = tree.makeTree('b1')
tree.link(a1, a2)
tree.link(a1, b1)
#act / assert
self.assertEqual(a1, tree.getRoot(a2))
self.assertEqual(a1, tree.getRoot(b1))
def test_link_connectsTwoTrees(self):
#arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
#act
tree.link(a1, a2)
#assert
self.assertEqual(a1, tree.getRoot(a2))
def test_makeRoot_flip_tree(self):
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
a4 = tree.makeTree('a4')
a5 = tree.makeTree('a5')
a6 = tree.makeTree('a6')
tree.link(a1, a2, 1)
tree.link(a2, a3, 2)
tree.link(a3, a4, 3)
tree.link(a4, a5, 4)
tree.link(a5, a6, 5)
b1 = tree.makeTree('b1')
b2 = tree.makeTree('b2')
b3 = tree.makeTree('b3')
tree.link(b1, b2)
tree.link(b2, b3)
tree.link(a3, b1)
#act
tree.makeRoot(b3)
#assert
self.assertEqual(b3, tree.getRoot(a6))
# nodes on the flipped path still share root
self.assertEqual(tree.getRoot(b1), tree.getRoot(a2))
# node in flipped path and node out of path share root
self.assertEqual(tree.getRoot(a6), tree.getRoot(a2))
self.assertEqual(b2, b1.represented_parent)
self.assertEqual(b3, b2.represented_parent)
self.assertEqual(b1, a3.represented_parent)
self.assertEqual(a3, a2.represented_parent)
self.assertEqual(a2, a1.represented_parent)
def test_link__preservesRepresentedParent(self):
''' after linking all these tree's the represented_parent nodes should represent the paths in the represented tree
'''
#Arrange
tree = LinkCutTree()
a1 = tree.makeTree('a1')
a2 = tree.makeTree('a2')
a3 = tree.makeTree('a3')
a4 = tree.makeTree('a4')
a5 = tree.makeTree('a5')
a6 = tree.makeTree('a6')
tree.link(a1, a2)
tree.link(a2, a3)
tree.link(a3, a4)
tree.link(a4, a5)
tree.link(a5, a6)
tree.access(a3)
c1 = tree.makeTree('c1')
c2 = tree.makeTree('c2')
c3 = tree.makeTree('c3')
tree.link(c1, c2)
tree.link(c2, c3)
tree.link(a4, c1)
# act/assert
self.assertEqual(a1, a2.represented_parent)
self.assertEqual(a2, a3.represented_parent)
self.assertEqual(a3, a4.represented_parent)
self.assertEqual(a4, a5.represented_parent)
self.assertEqual(a5, a6.represented_parent)
self.assertEqual(c1, c2.represented_parent)
self.assertEqual(c2, c3.represented_parent)
self.assertEqual(a4, c1.represented_parent)
def __init__(self):
self.forest = LinkCutTree()
self.time = 0
def test_getNode_nodeExists_returnsNode(self):
tree = LinkCutTree()
a1 = tree.makeTree('a1')
self.assertEqual(a1, tree.getNode('a1'))
def test_getNode_nodeDoesntExist_returnsNone(self):
tree = LinkCutTree()
self.assertIsNone(tree.getNode('a1'))
