Leetcode-flatten Binary Tree to Linked List

Given a binary tree, flatten it to a linked list in-place.

For example,
Given

         1        /        2   5      /\        3   4   6

The flattened tree should look like:

   1         2             3                 4                     5                         6

The approximate meaning of this question is to put the two-fork tree in place by sequential traversal sequence. For example, the ordinal traversal sequence of a two-fork tree is 1,2,3,4,5,6. Then, in tandem with the tree structure, is the binary tree below.

    public void Flatten (TreeNode root) {        if (root = null) return;        TreeNode left = Root.left;        TreeNode right = Root.right;        Root.left = null;        Flatten (left);        Flatten (right);        Root.right = left;        TreeNode cur = root;        while (cur.right! = null) cur = cur.right;        Cur.right = right;    }

The code is very straightforward, but it's not a good thought. Remember that the tree is due to its own recursive nature (as is the case with his definition). So, it's very good to handle it in a recursive way.

The general processing mode of the sensory tree is:

dispose of left; handle right; splice with Root.

Of course, the above is a sequential traversal, so the tree processing mode is basically the same as the tree traversal mode, basically is to transform three depth traversal and a hierarchical traversal algorithm. Remember, remember, remember!!!

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Leetcode-flatten Binary Tree to Linked List