#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;
using ld=long double;
ld pie=3.141592653589793;
ll inf=1444999999;
ll mod=1000000007;
int main(){
    string s;
    cin >> s;
    ll ans=inf;
    for (ll i = 0; i < s.size(); i++)
    {
        if (s[i]!='c')
        {
            continue;
        }
        ll w=0;
        for (ll j = i+1; j < s.size(); j++)
        {
            if (s[j]=='w')
            {
                w+=1;
                if (w==2)
                {
                    ans=min(ans,j-i+1);
                    break;
                }
            }
        }
    }
    if (ans==inf)
    {
        cout << -1 << endl;
    }else{
        cout << ans << endl;
    }
    
}