#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    string s;
    cin >> s;
    vector<int> ans;
    int flag = 0,tester = 0;
    for(int i = 0;i < s.length();i++){
        if(s[i] == 'c'){
            tester = 1;
            flag = 1;
        }
        else if(flag == 1 && s[i] == 'w'){
            flag = 2;
        }
        else if(flag == 2 && s[i] == 'w'){
            ans.push_back(tester);
            flag = 0;
        }
        if(flag > 0)tester++;
    }
    sort(ans.begin(), ans.end(),greater<int>());
    if(ans.size() == 0)cout << -1 << endl;
    else cout << ans[0] << endl;
    return 0;
}