import std.algorithm,
       std.string,
       std.range,
       std.stdio,
       std.conv;

ulong factorial(ulong n) {
  ulong t = 1;

  for (ulong i; i < n; i++)
    t *= (n - i);

  return t;
}

ulong p(ulong n, ulong r) {
  ulong t = 1;

  for (ulong i; i < r; i++)
    t *= (n - i);

  return t;
}

ulong c(ulong n, ulong r) {
  return p(n, r) / r.factorial; 
}

void main() {
  dchar[] cwws = readln.chomp.split(string.init).to!(dchar[]);
  size_t idx;
  size_t count;
  ulong ws;

  foreach_reverse (c; cwws) {
    if (cwws.length - 2 < idx) {
      break;
    }

    if (c == 'c') {
      count += ws.c(2);
    } else if (c == 'w'){
      ws++;
    }
    idx++;
  }

  writeln(count);
}