Univalued Binary Tree
A binary tree is univalued if every node in the tree has the same value.
Return true if and only if the given tree is univalued.
- Input: [1,1,1,1,1,null,1]
-
Output: true
- Input: [2,2,2,5,2]
- Output: false
Java Solution:
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public class Solution {
public boolean isUnivalTree(TreeNode root) {
int val = root.val;
if(root.left == null && root.right == null){
return true;
}
if(root.left == null){
return isUnivalTree(root.right) &&(root.val == root.right.val);
}
else if(root.right == null){
return isUnivalTree(root.left) &&(root.val == root.left.val);
}
else{
return isUnivalTree(root.left) && isUnivalTree(root.right)
&& (root.val == root.left.val) && (root.val == root.right.val);
}
}
}
