TList list_insert_ordered(TList list, TInfo x){

      TNode *curr = list;
      TNode *node;
      TNode *succ;

      curr->link = succ;

     while(curr!=NULL && greater(x,curr->info))
        {curr = curr->link;}

     if(curr==NULL)
        {node = node_create(x);
         assert(node!=NULL);
         node->link == list;
         return node;}
     else{
        node = node_create(x);
        assert(node!=NULL);
        node->link = succ;
        curr->link = node;
        return list;}
}