#include <bits/stdc++.h>
using namespace std;
#define rep(i, a) for (int i = 0; i < (a); i++)
#define rep2(i, a, b) for (int i = (a); i < (b); i++)
#define repr(i, a) for (int i = (a) - 1; i >= 0; i--)
#define repr2(i, a, b) for (int i = (b) - 1; i >= (a); i--)
template<class T1, class T2> bool chmin(T1 &a, T2 b) { return b < a && (a = b, true); }
template<class T1, class T2> bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
typedef long long ll;

bool is_chiwawa(string s) {
	int k = 0;
	for (char c : s) {
		if (k == 0 && c == 'c') k++;
		else if (k == 1 && c == 'w') k++;
		else if (k == 2 && c == 'w') k++;
	}
	return k == 3;
}

int main() {
	string s;
	cin >> s;
	int ans = 101010;
	rep(i, s.size()) for (int j = 1; i + j <= s.size(); j++) {
		if (is_chiwawa(s.substr(i, j))) chmin(ans, j);
	}
	if (ans == 101010) ans = -1;
	cout << ans << endl;
	return 0;
}