#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <functional>
#include <set>
#include <ctime>
#include <random>
using namespace std;
template<typename T> istream& operator >> (istream& is, vector<T>& vec){for(T& val: vec) is >> val; return is;}
template<typename T> istream& operator , (istream& is, T& val){ return is >> val;}
template<typename T> ostream& operator << (ostream& os, const vector<T>& vec){for(int i=0; i<vec.size(); i++) os << vec[i] << (i==vec.size()-1?"\n":" ");return os;}
template<typename T> ostream& operator , (ostream& os, T& val){ return os << " " << val;}
template<typename T> ostream& operator >> (ostream& os, T& val){ return os << " " << val;}

using namespace std;

int main(){
	string s;
	cin >> s;

	int ans = 114514;
	for(int i=0; i<s.size(); i++){
		if(s[i] == 'c') for(int j=i+1; j<s.size(); j++){
			if(s[j] == 'w') for(int k=j+1; k<s.size(); k++){
				if(s[k] == 'w') ans = min(ans, k-i+1);
			}
		}
	}
	if(ans == 114514) ans = -1;
	cout << ans << endl;
	return 0;
}