#include<stdio.h>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
#include <sstream>
#include <iostream>
#include <string>
#include <stdio.h>

using namespace std;

int main() {

	string S;
	cin >> S;

	int ans = 999, sta = 0;
	bool flag;

	for (int l = 0; l < S.size(); l++) {
		if (S[l] == 'c') {
			flag = false;
			for (int m = l + 1; m < S.size() - 1; m++) {
				if (S[m] == 'w' && !flag) {
					for (int r = m+1; r < S.size();  r++) {
						if (S[r] == 'w') {
							ans = min(ans, r-l+1);
							//cout << "l: " << l << " m: " << m << " r: " << r << " ans: " << ans << endl;
							flag = true;
							break;
						}
					}
					if (flag) break;
				}
			}
		}
	}

	if (ans == 999) cout << -1 << endl;
	else cout << ans << endl;

	return 0;
}