#include <bits/stdc++.h>
using namespace std;

int main()
{
    string s;
    cin >> s;
    int c = -1, cw = -1, cww = -1;
    for (int i = 0; i < s.size(); i++) {
        if (s.at(i) == 'c') {
            c = i;
        } else if (s.at(i) == 'w' && c != -1) {
            if (cw != -1) {
                if (cww == -1 || i - cw + 1 < cww) {
                    cww = i - cw + 1;
                }
            }
            cw = c;
        }
    }
    cout << cww << endl;
}