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

int main()
{
    string S;
    cin >> S;

    int N = S.size();
    int ans = 1e9;
    for (int i = 0; i < N; i++)
    {
        if (S[i] == 'c')
        {
            for (int j = i + 1; j < N; j++)
            {
                if (S[j] == 'w')
                {
                    for (int k = j + 1; k < N; k++)
                    {
                        if (S[k] == 'w')
                        {
                            ans = min(ans, k - i + 1);
                        }
                    }
                }
            }
        }
    }
    if (ans == 1e9)
    {
        cout << -1;
    }
    else
    {
        cout << ans;
    }
}