#include <iostream>
#include <string>
#include <limits>
#include <algorithm>

using namespace std;

int main() {
	string s;
	cin >> s;
	int result = numeric_limits<int>::max();
	for (size_t c = 0; c < s.size(); ++c) {
		if (s[c] != 'c') {
			continue;
		}
		for (size_t w1 = c + 1; w1 < s.size(); ++w1) {
			if (s[w1] != 'w') {
				continue;
			}
			for (size_t w2 = w1 + 1; w2 < s.size(); ++w2) {
				if (s[w2] != 'w') {
					continue;
				}
				result = min(result, (int)(w2 - c + 1));
			}
		}
	}
	if (result == numeric_limits<int>::max()) {
		result = -1;
	}
	cout << result << endl;
	return 0;
}