#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<map>
#define all(x) x.begin(),x.end()
#define pb push_back
#define ll long long 
#define P pair<int,int>
#define LP pair<ll,ll>
using namespace std;
int main() {
	string s;
	cin >> s;
	int len;
	int ans = numeric_limits<int>::max();
	bool f = 0;
	for (int i = 0; i <s.size(); i++) {
		for (int j = i + 1; j < s.size(); j++) {
			for (int k = j + 1; k < s.size(); k++) {
				if (s[i] == 'c' and s[j] == 'w' and s[k] == 'w') {
					len = k - i + 1;
					ans = min(ans, len);
				}
				
				
			}
		}
		
	}
	if (ans == numeric_limits<int>::max()) ans = -1;
	cout << ans<< endl;
	return 0;
}