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Java-based LeetCode algorithm problem solutions, regularly updated

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package g1301_1400.s1302_deepest_leaves_sum;

// #Medium #Depth_First_Search #Breadth_First_Search #Tree #Binary_Tree
// #2022_03_14_Time_5_ms_(59.50%)_Space_44.1_MB_(92.78%)

import com_github_leetcode.TreeNode;
import java.util.LinkedList;
import java.util.Objects;
import java.util.Queue;

/*
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
/**
 * 1302 - Deepest Leaves Sum\.
 *
 * Medium
 *
 * Given the `root` of a binary tree, return _the sum of values of its deepest leaves_.
 *
 * **Example 1:**
 *
 * ![](https://assets.leetcode.com/uploads/2019/07/31/1483_ex1.png)
 *
 * **Input:** root = [1,2,3,4,5,null,6,7,null,null,null,null,8]
 *
 * **Output:** 15
 *
 * **Example 2:**
 *
 * **Input:** root = [6,7,8,2,7,1,3,9,null,1,4,null,null,null,5]
 *
 * **Output:** 19
 *
 * **Constraints:**
 *
 * *   The number of nodes in the tree is in the range [1, 10⁴].
 * *   `1 <= Node.val <= 100`
**/
public class Solution {
    public int deepestLeavesSum(TreeNode root) {
        Queue queue = new LinkedList<>();
        queue.offer(root);
        int sum = 0;
        while (!queue.isEmpty()) {
            int size = queue.size();
            sum = 0;
            for (int i = 0; i < size; i++) {
                TreeNode curr = queue.poll();
                sum += Objects.requireNonNull(curr).val;
                if (curr.left != null) {
                    queue.offer(curr.left);
                }
                if (curr.right != null) {
                    queue.offer(curr.right);
                }
            }
        }
        return sum;
    }
}