Deepest Leaves Sum — LeetCode 1302 Python Solution
MediumTreeDepth-First SearchBreadth-First SearchBinary Tree
- Problem
- #1302
- Pattern
- Tree Traversal
- Reading time
- 3 min
- Source
- leetcode.com
The problem
Given the root of a binary tree, return the sum of values of its deepest leaves.
Example
- Input
- root = [1,2,3,4,5,null,6,7,null,null,null,null,8]
- Output
- 15
Python solution
Python
# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution:
def deepestLeavesSum(self, root: Optional[TreeNode]) -> int:
q = deque([root])
while q:
ans = 0
for _ in range(len(q)):
node = q.popleft()
ans += node.val
if node.left:
q.append(node.left)
if node.right:
q.append(node.right)
return ansComplexity
| Measure | Complexity |
|---|---|
| Time | O(n) |
| Space | O(n) auxiliary |
Pattern: Tree Traversal
Choose the order — preorder, inorder, postorder, level — and the problem solves itself. LeetCode 1302. Deepest Leaves Sum is filed here because LeetCode tags it Tree and Binary Tree, which is the vocabulary this hub collects.
The tree traversal guide has the Python template for the pattern and the 225 LeetCode problems that use it.
Related problems
Frequently asked questions
- How hard is LeetCode 1302. Deepest Leaves Sum?
- LeetCode 1302. Deepest Leaves Sum is rated Medium on LeetCode.
- What is the time complexity of LeetCode 1302. Deepest Leaves Sum?
- The Python solution on this page runs in O(n).
- What is the space complexity of LeetCode 1302. Deepest Leaves Sum?
- The Python solution on this page uses O(n) auxiliary space.
- What topics does LeetCode 1302. Deepest Leaves Sum cover?
- LeetCode 1302. Deepest Leaves Sum is tagged Tree, Depth-First Search, Breadth-First Search and Binary Tree on LeetCode.