/in/foo.cc: In function 'void insert(Node*&, long int)':
/in/foo.cc:28:77: error: 'struct Node' has no member named 'size'
     if(o==NULL) {o=new Node(v);o->v=v;o->ch[0]=o->ch[1]=NULL;o->r=rand();o->size=1;}
                                                                             ^~~~