Package g0101_0200.s0117_populating_next_right_pointers_in_each_node_ii

Class Solution

  • public class Solution
extends Object
    117 - Populating Next Right Pointers in Each Node II.

    Medium

    Given a binary tree

    struct Node { int val; Node *left; Node *right; Node *next; }

    Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL.

    Initially, all next pointers are set to NULL.

    Example 1:

    Input: root = [1,2,3,4,5,null,7]

    Output: [1,#,2,3,#,4,5,7,#]

    Explanation: Given the above binary tree (Figure A), your function should populate each next pointer to point to its next right node, just like in Figure B. The serialized output is in level order as connected by the next pointers, with ‘#’ signifying the end of each level.

    Example 2:

    Input: root = []

    Output: []

    Constraints:

    • The number of nodes in the tree is in the range [0, 6000].
    • -100 <= Node.val <= 100

    Follow-up:

    • You may only use constant extra space.
    • The recursive approach is fine. You may assume implicit stack space does not count as extra space for this problem.

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • connect

        public Node connect​(Node root)