Description
Given two binary trees root1 and root2, merge them into a new binary tree. For overlapping nodes, add the values. For non-overlapping, use the existing node.
Examples
Input:
root1 = [1,3,2,5], root2 = [2,1,3,null,4,null,7]Output:
[3,4,5,5,4,null,7]Explanation:
Merged values.
Input:
root1 = [1], root2 = [2,1,3,null,4,null,7]Output:
[1]Explanation:
Merging a single-node tree [1] with a larger tree. The root values are summed where nodes overlap.
Input:
root1 = [4,2,6,1,3], root2 = [3,1,5,null,null,4,7]Output:
[7,3,11,1,3,4,7]Explanation:
Both trees have multiple levels with overlapping nodes. Root nodes merge (4+3=7), left children merge (2+1=3), right children merge (6+5=11). Left subtree keeps node 1 from root1 and node 3 from root1, while right subtree gets node 4 from root2 and node 7 from root2.
Constraints
- •
0 ≤ nodes ≤ 2000