boolean isBanalced = true;
    public boolean IsBalanced_Solution(TreeNode root) {
        if(root == null){
            return true;
        }
        getHeight(root);
        return isBanalced;
    }
    
    private int getHeight(TreeNode node){
        if(node == null){
            return 0;
        }
         int left = getHeight(node.left);
        int right = getHeight(node.right);
        if(Math.abs(right - left) > 1){
            isBanalced = false;
        }
        return Math.max(left, right)+1;
    }
}