C  THIS PROGRAM IS ATTEMPTING TO DETERMINE WHETHER A REAL NUMBER
C  CAN BE USED AS THE LOOP INDEX OF A DO LOOP
        DO 10 I = 1,10,2
           WRITE (6, 11) I
   10   CONTINUE
   11   FORMAT (1X, I5)
        DO 20  X = 1, 5, 0.5
           WRITE (6, 12) X
   20   CONTINUE
   12   FORMAT (1X , F4.1)
        STOP
        END