public TreeNode ReverseTree(TreeNode root)
{
if (root == null)
return null;
Stack<TreeNode> treeStack = new Stack<TreeNode> ();
TreeNode newRoot = null;
while (root != null) {
treeStack.Push (root);
newRoot = root;
root = root.Left;
}
TreeNode deepLeft = newRoot;
TreeNode temp, right;
treeStack.Pop ();
while (treeStack.Count != 0) {
temp = treeStack.Pop ();
right = temp.Right;
deepLeft.Right = temp;
deepLeft.Left = right;
deepLeft = temp;
}
return newRoot;
}
public static void Main (string[] args)
{
TreeNode root = new TreeNode (1);
TreeNode nodeA = new TreeNode(2);
TreeNode nodeB = new TreeNode (3);
TreeNode nodeC = new TreeNode(4);
TreeNode nodeD = new TreeNode (5);
TreeNode nodeE = new TreeNode(6);
root.Left = nodeA;
root.Right = nodeB;
nodeA.Left = nodeC;
nodeC.Left = nodeD;
nodeC.Right = nodeE;
Reverser reverser = new Reverser ();
TreeNode newRoot = reverser.ReverseTree (root);
Console.WriteLine (newRoot.Value + " " + newRoot.Left.Value + " " + newRoot.Right.Value);
Console.WriteLine (newRoot.Right.Right.Value + " " + newRoot.Right.Right.Left.Value + " " + newRoot.Right.Right.Right.Value);
}
