character*100::pass
  character::c
  read *,pass
  do i=1,len_trim(pass)
     c = pass(i:i)
     if (c >= 'A' .and. c <= 'Z') then
        c = CHAR(ICHAR(c)+32)
     else
        c = CHAR(ICHAR(c)-32)
     end if
     pass(i:i) = c
  end do
  print '(a)',pass(1:len_trim(pass))
end program