#include <bits/stdc++.h>
using namespace std;
void _print(long long int t) { cerr << t; }
void _print(int t) { cerr << t; }
void _print(string t) { cerr << t; }
void _print(char t) { cerr << t; }
void _print(long double t) { cerr << t; }
void _print(double t) { cerr << t; }
void _print(long long unsigned t) { cerr << t; }
template <class T, class V>
void _print(pair<T, V> p);
template <class T>
void _print(vector<T> v);
template <class T>
void _print(set<T> v);
template <class T, class V>
void _print(map<T, V> v);
template <class T>
void _print(multiset<T> v);
template <class T, class V>
void _print(pair<T, V> p) {
  cerr << "{";
  _print(p.first);
  cerr << ",";
  _print(p.second);
  cerr << "}";
}
template <class T>
void _print(vector<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(set<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(multiset<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T, class V>
void _print(map<T, V> v) {
  cerr << "[ ";
  for (auto i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class c>
c gcd(c a, c b) {
  if (b == 0) return a;
  gcd(b, a % b);
}
template <class c>
c lcm(c a, c b) {
  return a / gcd(a, b) * b;
}
template <class a>
bool prime(a n) {
  for (a i = 2; i <= sqrt(n); i++) {
    if (n % i == 0) return 0;
  }
  return 1;
}
bool bigger(pair<int, int> picachu, pair<int, int> qicachu) {
  return (picachu.first < qicachu.first);
}
template <class a>
void printarr(a arr[], int n) {
  for (int i = 0; i < n; i++) cout << arr[i] << ' ';
  cout << '\n';
}
template <class c>
void printarr(vector<c> v) {
  int n = (int)v.size();
  for (int i = 0; i < n; i++) {
    cout << v[i] << ' ';
  }
  cout << '\n';
}
int chartoint(char c) {
  if (c >= 'a' && c <= 'z') return c - 'a';
  if (c >= 'A' && c <= 'Z') return c - 'A' + 26;
  return 52;
}
int kadane(int arr[], int n) {
  int maximum = arr[0];
  int max_so_far = 0;
  for (int i = 0; i < n; i++) {
    max_so_far += arr[i];
    if (max_so_far > maximum) maximum = max_so_far;
    if (max_so_far < 0) max_so_far = 0;
  }
  return maximum;
}
template <class a>
a powmod(a t1, a t2, a mod) {
  a res = 1;
  t1 = t1 % mod;
  if (t1 == 0) return 0;
  while (t2) {
    if (t2 & 1) res = (res * t1) % mod;
    t1 = (t1 * t1) % mod;
    t2 = t2 >> 1;
  }
  return res;
}
const long long int MOD = 1e9 + 7;
const int N = 1e5;
void run() {
  string s;
  cin >> s;
  int n = (int)s.size();
  long long int s1 = 0, s2 = 0, s3 = 0;
  for (int i = 0; i < n; i++) {
    if (s[i] == 'o') {
      s2 += s1;
    } else if (s[i - 1] == 'v' && i > 0) {
      s1++;
      s3 += s2;
    }
  }
  cout << s3 << '\n';
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  ;
  cout << setprecision(15) << fixed;
  { run(); }
  cerr << "time taken : " << (float)clock() / CLOCKS_PER_SEC << " secs" << '\n';
  return 0;
  ;
}
