LeetCode-in-Java
1302. Deepest Leaves Sum
Medium
Given the root of a binary tree, return the sum of values of its deepest leaves.
Example 1:
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
Solution
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;
* }
* }
*/
public class Solution {
public int deepestLeavesSum(TreeNode root) {
Queue<TreeNode> 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;
}
}