public void RedBlackTree_StressTest()
{
var nodeCount = 1000 * 10;
var rnd = new Random();
var randomNumbers = Enumerable.Range(1, nodeCount)
.OrderBy(x => rnd.Next())
.ToList();
var tree = new RedBlackTree <int>();
for (int i = 0; i < nodeCount; i++)
{
tree.Insert(randomNumbers[i]);
Assert.IsTrue(tree.Count == i + 1);
}
//shuffle again before deletion tests
randomNumbers = Enumerable.Range(1, nodeCount)
.OrderBy(x => rnd.Next())
.ToList();
//IEnumerable test using linq
Assert.AreEqual(tree.Count, tree.Count());
Assert.AreEqual(tree.Count, tree.AsEnumerableDesc().Count());
for (int i = 0; i < nodeCount; i++)
{
tree.Delete(randomNumbers[i]);
Assert.IsTrue(tree.Count == nodeCount - 1 - i);
}
Assert.IsTrue(tree.Count == 0);
}
public void RedBlackTree_BulkInit_Test_With_Node_LookUp()
{
var nodeCount = 1000;
var rnd = new Random();
var sortedNumbers = Enumerable.Range(1, nodeCount).ToList();
var tree = new RedBlackTree <int>(sortedNumbers, true);
Assert.IsTrue(tree.Root.IsBinarySearchTree(int.MinValue, int.MaxValue));
//IEnumerable test using linq
Assert.AreEqual(tree.Count, tree.Count());
Assert.AreEqual(tree.Count, tree.AsEnumerableDesc().Count());
tree.Root.VerifyCount();
for (int i = 0; i < nodeCount; i++)
{
tree.Delete(sortedNumbers[i]);
tree.Root.VerifyCount();
Assert.IsTrue(tree.Root.IsBinarySearchTree(int.MinValue, int.MaxValue));
var actualHeight = tree.Root.GetHeight();
//http://doctrina.org/maximum-height-of-red-black-tree.html
var maxHeight = 2 * Math.Log(nodeCount + 1, 2);
Assert.IsTrue(actualHeight < maxHeight);
Assert.IsTrue(tree.Count == nodeCount - 1 - i);
}
Assert.IsTrue(tree.Count == 0);
}
/// <summary>
/// Time complexity: O(nlog(n)).
/// </summary>
public static IEnumerable <T> Sort(IEnumerable <T> enumerable, SortDirection sortDirection = SortDirection.Ascending)
{
//create BST
var tree = new RedBlackTree <T>();
foreach (var item in enumerable)
{
tree.Insert(item);
}
return(sortDirection == SortDirection.Ascending ?
tree.AsEnumerable() : tree.AsEnumerableDesc());
}
public void RedBlackTree_Smoke_Test()
{
//insert test
var tree = new RedBlackTree <int>();
Assert.AreEqual(-1, tree.Root.GetHeight());
tree.Insert(1);
tree.Insert(2);
tree.Insert(3);
tree.Insert(4);
tree.Insert(5);
tree.Insert(6);
tree.Insert(7);
tree.Insert(8);
tree.Insert(9);
tree.Insert(10);
tree.Insert(11);
Assert.AreEqual(11, tree.Count);
//IEnumerable test using linq
Assert.AreEqual(tree.Count, tree.Count());
Assert.AreEqual(tree.Count, tree.AsEnumerableDesc().Count());
//delete
tree.Delete(1);
tree.Delete(2);
tree.Delete(3);
tree.Delete(4);
tree.Delete(5);
tree.Delete(6);
tree.Delete(7);
tree.Delete(8);
tree.Delete(9);
tree.Delete(10);
tree.Delete(11);
Assert.AreEqual(0, tree.Count);
}
public void RedBlackTree_Accuracy_Test()
{
var nodeCount = 1000;
var rnd = new Random();
var sorted = Enumerable.Range(1, nodeCount).ToList();
var randomNumbers = sorted
.OrderBy(x => rnd.Next())
.ToList();
var tree = new RedBlackTree <int>();
for (int i = 0; i < nodeCount; i++)
{
var index = tree.Insert(randomNumbers[i]);
Assert.AreEqual(index, tree.IndexOf(randomNumbers[i]));
Assert.IsTrue(tree.HasItem(randomNumbers[i]));
Assert.IsTrue(tree.Root.IsBinarySearchTree(int.MinValue, int.MaxValue));
tree.Root.VerifyCount();
var actualHeight = tree.Root.GetHeight();
//http://doctrina.org/maximum-height-of-red-black-tree.html
var maxHeight = 2 * Math.Log(nodeCount + 1, 2);
Assert.IsTrue(actualHeight < maxHeight);
Assert.IsTrue(tree.Count == i + 1);
}
for (int i = 0; i < sorted.Count; i++)
{
Assert.AreEqual(sorted[i], tree.ElementAt(i));
Assert.AreEqual(i, tree.IndexOf(sorted[i]));
}
//shuffle again before deletion tests
randomNumbers = Enumerable.Range(1, nodeCount)
.OrderBy(x => rnd.Next())
.ToList();
//IEnumerable test using linq
Assert.AreEqual(tree.Count, tree.Count());
Assert.AreEqual(tree.Count, tree.AsEnumerableDesc().Count());
for (int i = 0; i < nodeCount; i++)
{
if (rnd.NextDouble() >= 0.5)
{
var index = tree.IndexOf(randomNumbers[i]);
Assert.AreEqual(index, tree.Delete(randomNumbers[i]));
}
else
{
var index = tree.IndexOf(randomNumbers[i]);
Assert.AreEqual(tree.ElementAt(index), randomNumbers[i]);
tree.RemoveAt(index);
}
Assert.IsTrue(tree.Root.IsBinarySearchTree(int.MinValue, int.MaxValue));
tree.Root.VerifyCount();
var actualHeight = tree.Root.GetHeight();
//http://doctrina.org/maximum-height-of-red-black-tree.html
var maxHeight = 2 * Math.Log(nodeCount + 1, 2);
Assert.IsTrue(actualHeight < maxHeight);
Assert.IsTrue(tree.Count == nodeCount - 1 - i);
}
Assert.IsTrue(tree.Count == 0);
}
