public void Remove_TheRightChildWithNoChildren_TheRootWithNoChildren()
{
var firstNode = 2;
var secondNode = 3;
var bst = new BinarySearchTree <int, int>();
bst.Insert(Key(firstNode), Value(firstNode));
bst.Insert(Key(secondNode), Value(secondNode));
bst.Remove(Key(secondNode));
NodeAssert.NotNullAndEqual(bst.Root, Node(firstNode));
NodeAssert.BothChildrenAreNull(bst.Root);
}
public void Remove_TheRootElementWithLeftChild_NewRootIsTheLeftChild()
{
var firstNode = 2;
var secondNode = 1;
var bst = new BinarySearchTree <int, int>();
bst.Insert(Key(firstNode), Value(firstNode));
bst.Insert(Key(secondNode), Value(secondNode));
bst.Remove(Key(firstNode));
NodeAssert.NotNullAndEqual(bst.Root, Node(secondNode));
NodeAssert.BothChildrenAreNull(bst.Root);
}
public void Remove_TheRootFromAThreeLevelTree_TheCorrectTree()
{
var firstNode = Node(9);
var rootNode = ComplexTree.RootElement;
var bst = ComplexTree.Create();
bst.Remove(firstNode.Key);
bst.Remove(rootNode.Key);
NodeAssert.NotNullAndEqual(bst.Root, Node(10));
NodeAssert.BothChildrenAreNotNull(bst.Root);
NodeAssert.NotNullAndEqual(bst.Root.Right, Node(12));
NodeAssert.BothChildrenAreNotNull(bst.Root.Right);
NodeAssert.BothChildrenAreNull(bst.Root.Right.Left);
NodeAssert.BothChildrenAreNotNull(bst.Root.Right.Right);
NodeAssert.NotNullAndEqual(bst.Root.Left, Node(4));
NodeAssert.BothChildrenAreNotNull(bst.Root.Left);
NodeAssert.BothChildrenAreNotNull(bst.Root.Left.Left);
NodeAssert.BothChildrenAreNotNull(bst.Root.Left.Right);
}