#include <cstring>
#include <iostream>
#include <vector>
#include <string>
#include <map>
#include <queue>
#include <algorithm>

int main() {

  std::string str;
  std::cin >> str;

  int res = 10000;
  for(int begin = 0; begin < (int)str.size(); ++begin) {
    for(int end = begin + 1; end < (int)str.size(); ++end) {
      int flag = 0;
      for(int i = begin; i <= end; ++i) {
        if( flag == 0 and str[i] == 'c' ) {
          flag += 1;
          continue;
        }
        if( flag == 1 and str[i] == 'w' ) {
          flag += 1;
          continue;
        }
        if( flag == 2 and str[i] == 'w' ) {
          res = std::min(res, end - begin + 1);
          goto label_1;
        }
      }
    label_1:;
    }
  }

  if( res != 10000 ) {
    std::cout << res << std::endl;
  }
  else {
    std::cout << -1 << std::endl;
  }
  
  return 0;
}