struct Node{
  int data;
  Node* left;
  Node* right;
}

int findHeight(Node *root){
  if(root == NULL){ //base case
    return -1;
  }else{
    return max(findHeight(root->left), findHeight(root->right))+ 1;
  }
}

int max(int a, int b){
  if(a >= b) return a;
  else return b;
}