void insert( key, r )
     typekey key;  dataarray r;

     { extern int n;
       int i;
     i = hashfunction( key );
     if (empty(r[i])) /*** insert in main array ***/
               r[i].k = key;
          else /*** insert in new node ***/
               r[i].next = NewNode( key, r[i].next );
     n++;
     }