1430. Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree

https://leetcode.com/problems/check-if-a-string-is-a-valid-sequence-from-root-to-leaves-path-in-a-binary-tree

Description

Given a binary tree where each path going from the root to any leaf form a valid sequence, check if a given string is a valid sequence in such binary tree.

We get the given string from the concatenation of an array of integers arr and the concatenation of all values of the nodes along a path results in a sequence in the given binary tree.

Example 1:

**Input:** root = [0,1,0,0,1,0,null,null,1,0,0], arr = [0,1,0,1]
**Output:** true
**Explanation:**The path 0 -> 1 -> 0 -> 1 is a valid sequence (green color in the figure). 
Other valid sequences are: 
0 -> 1 -> 1 -> 0 
0 -> 0 -> 0

Example 2:

**Input:** root = [0,1,0,0,1,0,null,null,1,0,0], arr = [0,0,1]
**Output:** false 
**Explanation:** The path 0 -> 0 -> 1 does not exist, therefore it is not even a sequence.

Example 3:

**Input:** root = [0,1,0,0,1,0,null,null,1,0,0], arr = [0,1,1]
**Output:** false
**Explanation:** The path 0 -> 1 -> 1 is a sequence, but it is not a valid sequence.

Constraints:

• 1 <= arr.length <= 5000

• 0 <= arr[i] <= 9

• Each node's value is between [0 - 9].

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