Diameter of the tree

int height(Node*node)
{
    if(node==NULL)
      return 0;
      
    return 1+max(height(node->left),height(node->right));  
}




int diameter(Node* node)
{
     //pair<Node*,int>p=bfs(node);
     //pair<Node*,int>ans=bfs(p.first);
     
     //return ans.second;
     
     if(node==NULL)
       return 0;
     
     int a= height(node->left)+height(node->right);
     int b= diameter(node->left);
     int c= diameter(node->right);
     
     return max(a,max(b,c))+1;
}