#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <cstring>
#include <queue>
#include <stack>
#include <math.h>
#include <iterator>
#include <vector>
#include <string>
#include <set>
#include <math.h>
#include <iostream> 
#include<map>
#include <iomanip>
#include <stdlib.h>
#include <list>
#include <typeinfo>
#include <list>
#include <set>
using namespace std;
#define MAX_MOD 1000000007
#define REP(i,n) for(long long i = 0;i < n;++i)
#define LONGINF 1000000000000000000
int main() {
	string n;
	cin >> n;
	int ans = 1000;
	REP(i, n.length()) {
		if (n[i] == 'c') {
			bool hoge = 0;
			for (int q = i + 1;q < n.length();++q) {
				if (n[q] == 'w') {
					if (hoge == 1) {
						ans = min(ans, (int)q - (int)i);
						goto wow;
					}
					else {
						hoge = 1;
					}
				}
			}
		wow:;
		}
	}
	if (ans == 1000) {
		cout << "-1" << endl;
	}
	else cout << ans+1 << endl;
	return 0;
}