//---------------------------------------------------------------------
//------------- B F S + I T E R A T I V E -------------------
//---------------------------------------------------------------------
//BFS: Level-order Traversal, Queue
public List<List<int>> LevelOrderTraversal(TreeNode root)
{
List<List<int>> result = new List<List<int>>();
Queue<TreeNode> queue = new Queue<TreeNode>();
queue.Enqueue(root);
while (queue.Count != 0)
{
//Initiate a List<int> container for each level.
List<int> level = new List<int>();
//Store the static size as loop condition (this is a must because queue.Count is shrinking in each loop.)
int size = queue.Count;
for (int i = 0; i < size; i++)
{
//Dequeue each node
root = queue.Dequeue();
//Save the node value
level.Add(root.val);
//And enqueue its child at the same time
if (root.left != null) queue.Enqueue(root.left);
if (root.right != null) queue.Enqueue(root.right);
}
//Save the level after dequeue all the node.
result.Add(level);
}
return result;
}
static void Main(string[] args)
{
List<int> myList = new List<int>();
myList.Append(1);
myList.Append(2);
myList.Append(3);
Console.WriteLine(myList);
myList = new List<int>(3, 2, 1);
Console.WriteLine(myList);
myList = new List<int>(new System.Collections.Generic.List<int>(new int[] { 4, 3, 2, 1 }));
Console.WriteLine(myList);
Console.WriteLine(myList.Length);
Console.WriteLine(myList.Count());
myList.AppendRange(new System.Collections.Generic.List<int>(new int[] { 4, 3, 2, 1 }));
Console.WriteLine(myList);
Console.WriteLine(myList.Length);
Console.WriteLine(myList.Count());
Console.WriteLine(myList.ElementAt(2));
Console.WriteLine(myList.ElementAt(3));
Console.WriteLine(myList.IndexOf(3));
myList = new List<int>(10, 20, 30, 40);
myList.Insert(0, 8);
Console.WriteLine(myList);
myList = new List<int>(10, 20, 30, 40);
myList.Insert(1, 8);
Console.WriteLine(myList);
myList = new List<int>(10, 20, 30, 40);
myList.Insert(2, 8);
Console.WriteLine(myList);
myList = new List<int>(10, 20, 30, 40);
myList.Insert(4, 8);
Console.WriteLine(myList);
myList = new List<int>(10, 20, 30, 40);
myList.Insert(3, 7, 8, 9);
Console.WriteLine(myList);
myList.Remove(7);
Console.WriteLine(myList);
myList.Remove(10);
Console.WriteLine(myList);
myList.Remove(40);
Console.WriteLine(myList);
myList.Remove(9);
Console.WriteLine(myList);
myList.RemoveAt(1);
Console.WriteLine(myList);
myList.RemoveAt(1);
Console.WriteLine(myList);
myList = new List<int>(10, 20, 30, 40);
Console.WriteLine(myList);
myList.Sort();
Console.WriteLine(myList);
myList = new List<int>(2, 3, 1, 4);
Console.WriteLine(myList);
myList.Sort();
Console.WriteLine(myList);
myList = new List<int>(4, 3, 2, 1);
Console.WriteLine(myList);
myList.Sort();
Console.WriteLine(myList);
Random rand = new Random(); //static seed!
for (int i = 0; i < 20; i++)
{
myList = new List<int>();
for (int j = 0; j < i; j++)
myList.Append(rand.Next() % 100);
Console.WriteLine(myList);
myList.Sort();
Console.WriteLine(myList);
Console.WriteLine();
}
myList = new List<int>(4, 3, 2, 1);
foreach (int item in myList)
Console.WriteLine(item);
Console.WriteLine(myList[0]);
myList[1] = 8;
Console.WriteLine(myList[1]);
Console.WriteLine(myList[2]);
Console.WriteLine(myList[3]);
myList.RemoveAt(0);
myList.RemoveAt(0);
myList.RemoveAt(0);
myList.RemoveAt(0);
foreach (int item in myList)
Console.WriteLine(item);
Stack<int> myStack = new Stack<int>(1, 2, 3);
Console.WriteLine(myStack);
myStack.push(2);
Console.WriteLine(myStack);
Console.WriteLine(myStack.pop().ToString());
Console.WriteLine(myStack);
myStack.push(5);
myStack.push(4);
myStack.Sort();
Console.WriteLine(myStack);
Queue<int> myQueue = new Queue<int>(1, 2, 3);
Console.WriteLine(myQueue);
myQueue.enqueue(2);
Console.WriteLine(myQueue);
Console.WriteLine(myQueue.dequeue().ToString());
Console.WriteLine(myQueue);
myQueue.enqueue(5);
myQueue.enqueue(4);
myQueue.Sort();
Console.WriteLine(myQueue);
foreach (int item in myQueue)
{
Console.Write(item);
}
Console.WriteLine();
System.Collections.Generic.List<int> theirList = new System.Collections.Generic.List<int>();
theirList.Add(1);
theirList.Add(1);
theirList.Add(1);
theirList.Add(1);
var exit = Console.Read(); //DEBUG pause
}