// Q4 BFS
public static List<LinkedList> Tree2LinkedList(BinarySearchTree.Node Root)
{
List<LinkedList> Result;
if (Root == null)
return null;
else
{
Result = new List<LinkedList>();
Queue<BinarySearchTree.Node> Queue = new Queue<BinarySearchTree.Node>();
Queue<int> QLevels = new Queue<int>();
Queue.Enqueue(Root);
QLevels.Enqueue(0);
Result.Add(new LinkedList());
Result[0].Add(Root);
while (Queue.Count != 0)
{
BinarySearchTree.Node TempNode = Queue.Dequeue();
LinkedList TempLinkedList;
int Level = QLevels.Dequeue();
if (TempNode != null)
{
// Check if(TempNode) is CurrentLevel
if (TempNode.Left != null)
{
Queue.Enqueue(TempNode.Left);
QLevels.Enqueue(Level + 1);
}
if (TempNode.Right != null)
{
Queue.Enqueue(TempNode.Right);
QLevels.Enqueue(Level + 1);
}
if (Level + 1 != Result.Count)
{
if (TempNode.Left != null) Result.Last().Add(TempNode.Left);
if (TempNode.Right != null) Result.Last().Add(TempNode.Right);
}
else
{
TempLinkedList = new LinkedList();
if (TempNode.Left != null) TempLinkedList.Add(TempNode.Left);
if (TempNode.Right != null) TempLinkedList.Add(TempNode.Right);
if (TempNode.Right != null || TempNode.Left != null)
Result.Add(TempLinkedList);
}
}
}
return Result;
}
}
// Input: Root of the Tree
// Output: Printed Tree Level-by-level on Console
// Compute: Traverse and print the tree level-by-level
static void printTree(Node root)
{
// If the root node is null then return nothing
if (root == null)
{
return; // Do Nothing
}
int currentLevel = 0;
Queue<Node> q = new Queue<Node>(); // Error
Queue<int> qLevels = new Queue<int>();
q.Enqueue(root);
qLevels.Enqueue(0);
// Loop while there is an element in the queue
while (q.Count > 0)
{
Node temp = q.Dequeue();
int temLevel = qLevels.Dequeue();
// Printing node
if (temLevel != currentLevel)
{
System.Console.WriteLine("");
System.Console.Write(temp.Value);
currentLevel = temLevel;
}
else
{
if (temp == root)
{ // Special Case: If just the root don't print ", "
System.Console.Write(temp.Value);
}
else
{
System.Console.Write(", " + temp.Value);
}
}
if (temp.Left != null)
{
q.Enqueue(temp.Left);
qLevels.Enqueue(currentLevel+1);
}
if (temp.Right != null)
{
q.Enqueue(temp.Right);
qLevels.Enqueue(currentLevel+1);
}
}
}