#include <iostream>
#include <limits>

/*
 * [No.345 最小チワワ問題 - yukicoder](http://yukicoder.me/problems/984 "No.345 最小チワワ問題 - yukicoder")
 * 提出者 : まろ<marony@binbo-kodakusan.com>
 * 使用言語 C++
 */
using namespace std;

auto chiwawa_length(int start, string s) -> size_t {
    auto index = s.find('w', start + 1);
    if (index != (size_t)-1)
        index = s.find('w', index + 1);

    if (index == (size_t)-1)
        return -1;

    return index - start + 1;
}

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

    char c = 'c';
    auto index = s.find(c);
    auto min_length = numeric_limits<size_t>::max();
    while (index != (size_t)-1) {
        min_length = min(chiwawa_length(index, s), min_length);
        index = s.find(c, index + 1);
    }

    if (min_length == numeric_limits<size_t>::max())
        cout << -1 << endl;
    else
        cout << min_length << endl;

    return 0;
}