public static IEnumerable<TreeNode> BinaryNodeToTreeChildren(Node binaryTree)
{
Node binNode = binaryTree;
while (binNode != null)
{
yield return BinaryTreeToTree(binNode.Left);
binNode = binNode.Right;
}
}
// print a binary tree as arbitrary tree
public static string TreeString(Node node)
{
var sb = new StringBuilder();
Action<Node> f = null;
f = n =>
{
sb.Append("{");
for (Node child = n.Left; child != null; child = child.Right)
{
f(child);
}
sb.Append("}");
};
// build a new binary tree,
// whose root has the original binary tree as left node, and null right node.
f(new Node(node, null));
return sb.ToString();
}
// repr a binary tree as string.
public static string BinaryTreeString(Node node)
{
var sb = new StringBuilder();
Action<Node> f = null;
f = n =>
{
if (n == null)
{
sb.Append("x");
}
else {
sb.Append("(");
f(n.Left);
f(n.Right);
sb.Append(")");
}
};
f(node);
return sb.ToString();
}
public Node(Node left, Node right)
{
this.Left = left;
this.Right = right;
}
// convert a binary tree to an arbitrary tree
public static TreeNode BinaryTreeToTree(Node binaryTree)
{
if (binaryTree == null) return null;
return new TreeNode(BinaryNodeToTreeChildren(binaryTree));
}