public void TestBSTRemove()
{
var tree = new BinarySearchTree<int>() { 40, 11, 62, 43, 34, 16, 10, 63 };
Assert.IsTrue(tree.Contains(43), "\nChecking if 43 is there.");
Assert.IsTrue(tree.Remove(43), "\nRemoving 43.");
Assert.IsFalse(tree.Contains(43), "\nChecking if 43 is still there.");
}
public static void Main(string[] args)
{
Console.OutputEncoding = Encoding.UTF8;
BinarySearchTree <int> tree = new BinarySearchTree <int>();
tree.Root = new BinaryTreeNode <int>()
{
Data = 100
};
tree.Root.Left = new BinaryTreeNode <int>()
{
Data = 50, Parent = tree.Root
};
tree.Root.Right = new BinaryTreeNode <int>()
{
Data = 150, Parent = tree.Root
};
tree.Count = 3;
VisualizeTree(tree, "The BST with three nodes (50, 100, 150):");
tree.Add(75);
tree.Add(125);
VisualizeTree(tree, "The BST after adding two nodes (75, 125):");
tree.Add(25);
tree.Add(175);
tree.Add(90);
tree.Add(110);
tree.Add(135);
VisualizeTree(tree, "The BST after adding five nodes (25, 175, 90, 110, 135):");
tree.Remove(25);
VisualizeTree(tree, "The BST after removing the node 25:");
tree.Remove(50);
VisualizeTree(tree, "The BST after removing the node 50:");
tree.Remove(100);
VisualizeTree(tree, "The BST after removing the node 100:");
Console.Write("Pre-order traversal:\t");
Console.Write(string.Join(", ", tree.Traverse(TraversalEnum.PREORDER).Select(n => n.Data)));
Console.Write("\nIn-order traversal:\t");
Console.Write(string.Join(", ", tree.Traverse(TraversalEnum.INORDER).Select(n => n.Data)));
Console.Write("\nPost-order traversal:\t");
Console.Write(string.Join(", ", tree.Traverse(TraversalEnum.POSTORDER).Select(n => n.Data)));
tree.Remove(90);
VisualizeTree(tree, "---");
tree.Remove(75);
VisualizeTree(tree, "---");
tree.Remove(125);
VisualizeTree(tree, "---");
tree.Remove(110);
VisualizeTree(tree, "---");
tree.Remove(175);
VisualizeTree(tree, "---");
tree.Remove(135);
VisualizeTree(tree, "---");
tree.Remove(150);
VisualizeTree(tree, "---");
Console.ReadLine();
}
public void TestRemove()
{
BinarySearchTree<int> tree = new BinarySearchTree<int>();
//fails to remove item from empty list.
Assert.IsFalse(tree.Remove(10));
tree.Add(10);
tree.Add(12);
Assert.IsTrue(tree.Remove(10));
Assert.IsFalse(tree.Contains(10));
Assert.IsFalse(tree.Remove(10));
}
public void testMassAddRemove()
{
BinarySearchTree<int> tree = new BinarySearchTree<int>();
List<int> list = new List<int>();
Random r = new Random();
int numberToAdd = r.Next(1000000);
for (int i = 0; i < 1000; i++)
{
while (list.Contains(numberToAdd))
{
numberToAdd = r.Next(1000000);
}
list.Add(numberToAdd);
tree.Add(numberToAdd);
}
Assert.IsTrue(list.Count == tree.Count && list.Count == 1000);
list.Sort();
Assert.IsTrue(Enumerable.SequenceEqual(list, tree));
int curr;
for (int i = 0; i < list.Count; i++)
{
curr = list.ElementAt(0);
Assert.IsTrue(list.Remove(curr));
Assert.IsTrue(tree.Remove(curr));
}
Assert.IsTrue(Enumerable.SequenceEqual(list, tree));
numberToAdd = r.Next(1000000);
for (int i = 0; i < 1000; i++)
{
while (list.Contains(numberToAdd))
{
numberToAdd = r.Next(1000000);
}
list.Add(numberToAdd);
tree.Add(numberToAdd);
if (i % 2 == 0)
{
curr = list.ElementAt(r.Next(list.Count));
Assert.IsTrue(list.Remove(curr));
Assert.IsTrue(tree.Remove(curr));
}
}
list.Sort();
Assert.IsTrue(Enumerable.SequenceEqual(list, tree));
}
public void TestIterator()
{
BinarySearchTree<int> tree = new BinarySearchTree<int>();
//empty tree should give no iterations.
foreach (int curr in tree)
{
Assert.Fail("Should be empty.");
}
for(int i = 0; i < 100; i++) {
tree.Add(i);
}
int element = 0;
foreach(int curr in tree) {
Assert.AreEqual(element, curr);
element++;
}
//remove root element, an item with 1 child in the middle and a leaf with no children at bottom. Recheck everything iterates in order.
tree.Remove(0);
tree.Remove(50);
tree.Remove(100);
element = 1;
foreach (int curr in tree)
{
Assert.AreEqual(element, curr);
if (element == 49)
element += 2;
else
element++;
}
//re add 50 so that 51 now has child on left of 50 and child right of 52.
tree.Add(50);
element = 1;
foreach (int curr in tree)
{
Assert.AreEqual(element, curr);
element++;
}
//remove node with 2 children, check iterates correctly still.
tree.Remove(51);
element = 1;
foreach (int curr in tree)
{
Assert.AreEqual(element, curr);
if (element == 50)
element += 2;
else
element++;
}
}
public void TestCount()
{
BinarySearchTree<int> tree = new BinarySearchTree<int>();
Assert.IsTrue(tree.Count == 0);
tree.Add(10);
Assert.IsTrue(tree.Count == 1);
for (int i = 100; i < 200; i++)
{
tree.Add(i);
}
Assert.IsTrue(tree.Count == 101);
tree.Remove(10);
Assert.IsTrue(tree.Count == 100);
for (int i = 100; i < 200; i++)
{
tree.Remove(i);
}
Assert.IsTrue(tree.Count == 0);
//count isnt decremented if unsuccessfully try to remove an item.
tree.Remove(10);
Assert.IsTrue(tree.Count == 0);
}
