C234567
       WRITE (6, 39)
       WRITE (6, 40)
       WRITE (6, 41)
       WRITE (6, 42)
  39   FORMAT (1X, ' This program will get 3 integers from the user.')
  40   FORMAT (1X, ' It will echo them out. ')
       WRITE (6, 17)
  41   FORMAT (1X, ' It will then arrange them into descending order.')
  42   FORMAT (1X, ' It will print the sorted numbers.')
       WRITE (6, 17)
  17   FORMAT (1X, '    ')
       CALL GET3 (NUM1, NUM2, NUM3)
       WRITE (6, 17)
       WRITE (6, 43)
  43   FORMAT (' ', ' Here are the 3 numbers input by the user ')
       CALL PRIN3 (NUM1, NUM2, NUM3)
       CALL SORT3 (NUM1, NUM2, NUM3)
       WRITE (6, 17)
       WRITE (6, 44)
  44   FORMAT (' ', ' Here are the 3 numbers in descending order ')
       CALL PRIN3 (NUM1, NUM2, NUM3)
       STOP
       END

       SUBROUTINE GET3 (GA, GB, GC)
       INTEGER GA, GB, GC

       WRITE (6, 12)
       WRITE (6, 28)
       READ (5, 13,ERR = 25) GA, GB, GC
       GOTO 38
   25  WRITE (6, 14)
   12  FORMAT (1X, ' Please enter 3 integers which are ')
   28  Format (1X, ' right justified in columns 5,10,15 ')
   13  FORMAT (3I5)
   14  FORMAT (1X, //,'  INPUT DATA WAS ERRONEOUS - OUTPUT MEANINGLESS')
   38  RETURN
       END
       
       SUBROUTINE SWAP2(IA, IB)
       ITEMP = IA
       IA    = IB
       IB    = ITEMP
       RETURN
       END
       
       SUBROUTINE SORT3 (MA, MB, MC)
       IF (MA .LT. MB) CALL SWAP2 (MA, MB)
       IF (MB .LT. MC) CALL SWAP2 (MB, MC)
       IF (MA. LT. MB) CALL SWAP2 (MA, MB)
       RETURN
       END

       SUBROUTINE PRIN3 (PA,PB,PC)
       INTEGER PA, PB,PC

       WRITE (6, 29) PA, PB, PC
  29   FORMAT (1X, I20, I20, I20)
       RETURN
       END