#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(0), cin.tie(0);
  string s;
  cin >> s;
  int countV = 0;
  bool lastV = false;
  unsigned long long ans = 0;
  long long available = 0;
  for (int i = 0; i < s.length(); i++) {
    if (s[i] == 'v') {
      if (lastV) {
        ans += available;
        countV++;
      }
      lastV = true;
    } else {
      available += countV;
      lastV = false;
    }
  }
  cout << ans << "\n";
  return 0;
}
