#include <algorithm>
#include <iostream>
#include <iomanip>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <cmath>
using namespace std;

#define FOR(i,s,e) for (int i = int(s); i != int(e); i++)
#define FORIT(i,c) for (typeof((c).begin()) i = (c).begin(); i != (c).end(); i++)
#define ISEQ(c) (c).begin(), (c).end()

int main(){
	string s;
	cin >> s;

	int len = s.length();
	int min = -1;
	for(int i = 0;i < len;i++){
		if (s[i] == 'c'){
			int count = 0;
			for (int j = i+1;j < len;j++){
				if (s[j] == 'w') count++;
				if (count == 2){
					if (min == -1 || min > j - i + 1) min = j - i + 1;
					break;
				}
			}
		}
	}

	cout << min << endl;
	return 0;
}