#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	string S;
	cin >> S;
	int ans = INF;
	string cww = "cww";
	REP(i, S.size()) FOR(j, i + 1, S.size() + 1) {
		int state = 0;
		FOR(k, i, j) {
			if (state == 3) break;
			if (cww[state] == S[k]) ++state;
		}
		if (state == 3) chmin(ans, j - i);
	}
	if (ans == INF) puts("-1");
	else cout << ans << endl;
}