Level Order Traversal

Problem Statement Given the root of a binary tree, return the level order traversal of its nodes' values. (i.e., process the nodes from left to right, level by level). The traversal should return a list of lists, where each inner list contains the values of the nodes at that specific depth level. Input Specification The input is a binary tree defined by a level order array representation (where null or N represents an empty node). In the function signature, this corresponds to the root node of the tree. Output Specification Return a list of lists (e.g., List<List<Integer or vector<vector<int ), where the $i$ th list contains the values of nodes at the $i$ th level of the tree. Constraints The number of nodes in the tree is in the range $[0, 2000]$. 1000 ≤ Node.val ≤ 1000 Sample Test Cases Sample Input 1 Tree Visualization: Sample Output 1 Sample Input 2 Sample Output 2 Sample Input 3 Sample Output 3 Difficulty Level Easy