int search( key, r )
     typekey key;  dataarray r;

     { int high, i, low;
     for ( low=(-1), high=n;  high-low > 1;  )
          {
          i = (high+low) / 2;
          if ( key <= r[i].k )  high = i;
               else             low  = i;
          }
     if ( key==r[high].k )  return( high );
          else              return( -1 );
     }