Given the root of a binary tree and an integer targetSum, return all root-to-leaf paths where the sum of the node values equals targetSum. Pattern focus: Root To Leaf Paths. Carry the current path and backtrack after exploring each branch.
root = binary tree root, targetSum = required sum
all root-to-leaf paths that sum to targetSum
Example 1:
Input:
root = [5,4,8,11,null,13,4,7,2,null,null,5,1] targetSum = 22
Output:
[[5,4,11,2],[5,8,4,5]]
Explanation:
There are two root-to-leaf paths with sum 22.
Example 2:
Input:
root = [1,2,3] targetSum = 4
Output:
[[1,3]]
Explanation:
Only the path 1 -> 3 sums to 4.