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Connect Level Order Siblings (medium)

Problem Statement

Given a root of the binary tree, connect each node with its level order successor. The last node of each level should point to a null node.

Examples

Example 1:

  • Input: root = [1, 2, 3, 4, 5, 6, 7]
Image
  • Output: 
    [1 -> null]
[2 -> 3 -> null]
[4 -> 5 -> 6 -> 7 -> null]
  • Explanation:
    The tree is traversed level by level using BFS. Each node is connected to its next right node at the same level. The last node of each level points to null.

Example 2:

  • Input: root = [12, 7, 1, 9, null, 10, 5]
Image
  • Output: 
    [12 -> null]
[7 -> 1 -> null]
[9 -> 10 -> 5 -> null]
  • Explanation:
    The nodes are connected to their next right sibling at the same level. The last node of each level points to null.

Constraints:

  • The number of nodes in the tree is in the range [0, 2<sup>12</sup> - 1].
  • -1000 <= Node.val <= 1000

Try it yourself

Try solving this question here:

Python3
Python3
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