program exf1  ! exf1.f90 simple output of integer, string, floating point
              ! ! makes rest of line a comment
              ! & at end of line makes next line a continuation
  implicit none
  integer :: i = 7     ! declare variable i with initial value 7
  character :: ac = 'a'   ! a single character
  character (len=13) :: msg = "sample string"
  real :: x = 37.95      ! 32 bit float 
  double precision :: y = 127.34e10; ! 64 bit double precision
    
  print *, "exf1.f90"
  print *, "i=", i
  print *, "ac=", ac
  print *, "msg=", msg
  print *, "x=", x
  print *, "y=", y

  ! or you can specify a format, must have a statement number
    write(6,90) i
90  format('i=',i6)
    write(6,92) x 
92  format('x=',f12.2)
    write(6,93) y 
93  format('y=',e12.2)

end program exf1