#include<bits/stdc++.h>
#define rep(i, x) for(ll i = 0; i < x; i++)
#define rep2(i, x) for(ll i = 1; i <= x; i++)
#define all(a) (a).begin(),(a).end()
using ll = long long;
using ld = long double;
const ll INF = 10000000000000000;
using namespace std;
signed main() {
	string s; cin >> s; ll n = s.size(), ans = INF;
	rep(i, n) {
		if (s[i] == 'c') {
			ll w = 0, cnt = 0; bool flag = false;
			for (int j = i; j < n; j++) {
				cnt++;
				if (s[j] == 'w') { w++; }
				if (w == 2) { flag = true; break; }
			}
			if (flag) { ans = min(ans, cnt); }
		}
	}
	if (ans == INF) { cout << -1 << endl; return 0; }
	cout << ans << endl;
	return 0;
}