|
{
System.Console.Write(node.value + " ");
pre = node;
stack.Pop();
}
else
{
if (node.right != null)
stack.Push(node.right);
if (node.left != null)
stack.Push(node.left);
}
}
}
/// <summary>
/// 后续遍历循环实现2
/// </summary>
/// <param name="tree"></param>
public static void PostOrderLoop2(BinaryTreeNode tree)
{
HashSet<BinaryTreeNode> visited = new HashSet<BinaryTreeNode>();
Stack<BinaryTreeNode> stack = new Stack<BinaryTreeNode>();
BinaryTreeNode node = tree;
while (node != null || stack.Any())
{
if (node != null)
{
stack.Push(node);
node = node.left;
}
else
{
var item = stack.Peek();
if (item.right != null && !visited.Contains(item.right))
{
node = item.right;
}
else
{
System.Console.Write(item.value + " ");
visited.Add(item);
stack.Pop();
}
}
}
}
&nb |