character*10::A,B
  integer::char_num(27)
  integer::pos_a,pos_b
  data char_num/27*0/
  read *,A,B
  do i=1,len_trim(A)
     pos_a = ICHAR(A(i:i))-ICHAR('a') + 1
     pos_b = ICHAR(B(i:i))-ICHAR('a') + 1
     char_num(pos_a) = char_num(pos_a) + 1
     char_num(pos_b) = char_num(pos_b) - 1
  end do
  do i=1,27
     if (char_num(i).ne.0) then
        print '(a)',"NO"
        return
     end if
  end do
  print '(a)',"YES"
end program