* Simple examples using all data types and type converversions.
    
      program types
      
      integer i
      real r
      double precision d
      logical b
      character c
      
      i = 21
      i = i + i
      write(*, *) i
      
      r = 12E0 * -33E-1 + 3.15
      write(*, *) r
      
      d = 1D-10 + 5.1D0 * 1.234D15
      write(*, *) d
      
      b = .false.
      b = b .and. .true. .or. .not. (b .and. 10 .lt. 5)
      write(*, *) b
      
      c = 'a'
      write(*, *) c
      
      write(*, *) 'Type conversions'  
      i = int(r)
      write(*, *) i
      r = real(i)
      write(*, *) r
      r = real(d)
      write(*, *) r
      d = dble(r)
      write(*, *) d
      d = dble(i)
      write(*, *) d      
      i = ichar(c) + 1
      write(*, *) i
      c = char(i)
      write(*, *) c
      
      stop
      end