#include<bits/stdc++.h>
using namespace std;

int main(){
  string s;
  std::cin >> s;
  vector<int> p;
  for (int i = 0; i < s.length(); i++) {
    if(s[i] == 'c')p.push_back(i);
  }
  int ans = 1e9;
  for (int i = 0; i < p.size(); i++) {
    int cnt = 0;
    for (int j = p[i]; j < s.length(); j++) {
      if(s[j] == 'w')cnt++;
      if(cnt == 2)ans = min(ans, j - p[i] + 1);
    }
  }
  if(ans != 1e9)std::cout << ans << std::endl;
  else std::cout << -1 << std::endl;
  return 0;
}