#include <bits/stdc++.h>
using namespace std;
int main() {
  string a;
  int i;
  long long s = 0, t = 0, l = 0;
  cin >> a;
  for (i = 1; i < a.length(); i++) {
    if (a[i] == 'v' && a[i - 1] == 'v') {
      s += t;
      l++;
    }
    if (a[i] == 'o') t += l;
  }
  cout << s << endl;
  return 0;
}
