#include <iostream>
#include <cmath>
#include <string>
#include <vector>
#include <map>
#include <list>
#include <deque>
#include <algorithm>
#include <iomanip>

using namespace std;

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

	int ans = S.length() + 1;

	for (int i = 0; i < S.length(); i++) {
		if (S[i] == 'c') {
			int w = 0;
			for (int j = i + 1; j < S.length(); j++) {
				if (S[j] == 'w') w++;
				if (w == 2) {
					ans = min(ans, j - i + 1);
					break;
				}
			}
		}
	}

	if (ans == S.length() + 1) ans = -1;
	cout << ans << endl;
	return 0;
}