/* Day 6: Pgm 6.4               */
  /* simple program without input */

  /*                              */
  /*** add some put statements  ***/
  /***  to see PDV information  ***/
  /*                              */
   data a ;
     put 'first' _all_ ;
    u = x*4 ;
     put 'second' _all_ ;
    input x ;   * read in some data ;
    y = x*4 ;
    n = _n_ ;
     put 'third' _all_ ;
    output ;    * write obs in dataset a ;
    x = x + 1 ;
    n = _n_ ;
     put 'fourth' _all_ ;
    output ;    * write another obs in dataset a ;
   cards ;
    3
    -7
    5
 ;
   proc print data=a ;
    title 'May 29, pgm 6.3' ;
 run ;