Medium
Quiz
#117 Populating Next Right Pointers in Each Node II
APPROACH
An arbitrary binary tree is given using the node structure below:
struct Node {
int val;
Node *left;
Node *right;
Node *next;
}
Connect each node's next pointer to its immediate right neighbor on the same level. If no such node exists, set next to NULL.
All next pointers start as NULL.
Example 1:
struct Node {
int val;
Node *left;
Node *right;
Node *next;
}
Example 2:
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 3:
Input: root = []
Output: []
1 of 4
1:00
What is the optimal approach for this problem?