/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
class Solution {
int ans=0;
public int findTilt(TreeNode root) {
f(root);
return ans;
}
public int f(TreeNode root){
if(root==null) return 0;
int x=f(root.left);
int y=f(root.right);
ans=ans+Math.abs(x-y);
return x+y+root.val;
}
}