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

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


	int min = 1000;
	for (int i = 0; i < s.length(); i++) {
		if (s[i] == 'c') {
			for (int j = i; j < s.length(); j++) {
				if (s[j] == 'w') {
					for (int k = j + 1; k < s.length(); k++) {
						if (s[k] == 'w') {
							min = std::min(min, k - i + 1);
						}
					}
				}
			}
		}
	}

	if (min == 1000) {
		std::cout << -1 << std::endl;
		return 0;
	}
	std::cout << min << std::endl;
	return 0;
}