Univalued Binary Tree
A binary tree is uni-valued if every node in the tree has the same value.
Given the root of a binary tree, return true if the given tree is uni-valued, or false otherwise.
Example 1
1
/ \
1 1
/ \ \
1 1 1Input
root = [1,1,1,1,1,null,1]Output
trueEvery node in the tree has the value 1, so the tree is uni-valued.
Example 2
2
/ \
2 2
/ \
5 2Input
root = [2,2,2,5,2]Output
falseThe tree contains a node with value 5 while the other nodes have value 2, so it is not uni-valued.
Constraints
- The number of nodes in the tree is in the range
[1, 100]. 0 <= Node.val < 100