437. Path Sum III
Medium
30 Points
Tree
Depth-First Search
Binary Tree
Given the root of a binary tree and an integer targetSum, return the number of paths where the sum of the values along the path equals targetSum.
The path does not need to start or end at the root or a leaf, but it must go downwards (i.e., traveling only from parent nodes to child nodes).
Examples
Example 1
Input: root = [10,5,-3,3,2,null,11,3,-2,null,1], targetSum = 8
Output: 3
Explanation: The paths that sum to 8 are shown.
Example 2
Input: root = [5,4,8,11,null,13,4,7,2,null,null,5,1], targetSum = 22
Output: 3
Constraints
The number of nodes in the tree is in the range [0, 1000].-109 <= Node.val <= 109-1000 <= targetSum <= 1000
437. Path Sum III
Medium
30 Points
Tree
Depth-First Search
Binary Tree
Given the root of a binary tree and an integer targetSum, return the number of paths where the sum of the values along the path equals targetSum.
The path does not need to start or end at the root or a leaf, but it must go downwards (i.e., traveling only from parent nodes to child nodes).
Examples
Example 1
Input: root = [10,5,-3,3,2,null,11,3,-2,null,1], targetSum = 8
Output: 3
Explanation: The paths that sum to 8 are shown.
Example 2
Input: root = [5,4,8,11,null,13,4,7,2,null,null,5,1], targetSum = 22
Output: 3
Constraints
The number of nodes in the tree is in the range [0, 1000].-109 <= Node.val <= 109-1000 <= targetSum <= 1000