#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main() {
    string s;
    
    cin >> s;
    
    vector<int> c_id;
    for (int i = 0; i < s.length(); i++) {
        if (s[i] == 'c') {
            c_id.push_back(i);
        }
    }
    
    int cww_len = 1000;
    for (int i : c_id) {
        int ct_w = 0;
        for (int j = i + 1; j < s.length(); j++) {
            if (s[j] == 'w') {
                ct_w++;
                if (ct_w == 2) {
                    cww_len = min(cww_len, j - i + 1);
                }
            }
        }
    }
    
    if (cww_len == 1000)
    {
        cout << -1 << endl;
    } else {
        cout << cww_len << endl;    
    }
    
    return 0;
}