Package g0401_0500.s0437_path_sum_iii

Class Solution

java.lang.Object
g0401_0500.s0437_path_sum_iii.Solution
public class Solution extends java.lang.Object
437 - Path Sum III.

Medium

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).

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

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    helper(TreeNode node, int targetSum, long currSum)
     
    int
    pathSum(TreeNode root, int targetSum)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • pathSum

      public int pathSum(TreeNode root, int targetSum)

    • helper

      public void helper(TreeNode node, int targetSum, long currSum)