#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  string s;
  cin >> s;
  long long int n = s.size();
  long long int pos[n + 1];
  long long int cnt = 0;
  pos[0] = 0;
  for (long long int i = 1; i < n; i++) {
    pos[i] = pos[i - 1];
    if (s[i] == 'v' and s[i - 1] == 'v') {
      cnt++;
      pos[i] = cnt;
    }
  }
  long long int ans = 0;
  for (long long int i = 0; i < n; i++) {
    if (s[i] == 'o') {
      ans += pos[i] * (cnt - pos[i]);
    }
  }
  cout << ans << endl;
  return 0;
}
