#include <iostream>
#include <vector>
using namespace std;
const int INF = 1e9 + 7;
string s;
int a = INF, n;

int main()
{
    cin >> s;
    n = s.size();
    for (int i = 0; i < n; i++)
    {
        if (s[i] != 'c')
            continue;
        for (int j = i + 1; j < n; j++)
        {
            if (s[j] != 'w')
                continue;
            for (int k = j + 1; k < n; k++)
            {
                if (s[k] == 'w')
                    a = min(k - i + 1, a);
            }
        }
    }
    if (a == INF)
        a = -1;
    cout << a << endl;
}