program main
  implicit none
  integer*8::N,w,nw,i,comb,total
  character*100000::S
  read *,S
  nw = -1
  comb = 0
  total = 0
  do i=LEN_TRIM(S),1,-1
     if(S(i:i).eq.'w') then
        nw = nw + 1
        comb = comb + nw
     else if(S(i:i).eq.'c') then
        total = total + comb
     end if
  end do
  print '(i0)', total
end program main