character(len=100000)::str
  integer,parameter::zero=ICHAR('0'),nine=ICHAR('9')
  integer::digits(zero:nine),i,total=1
  data digits/10*0/
  read *, str
  do i=1,LEN_TRIM(str)
     digits(ICHAR(str(i:i))) = digits(ICHAR(str(i:i))) + 1
  end do
  do i=nine, zero, -1
     if(digits(i).eq.0) cycle
     str(total:total+digits(i)-1)=REPEAT(CHAR(i),digits(i))
     total = total + digits(i)
  end do
  print '(a)', TRIM(str)
end program