#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
using ll = long long ;
using P = pair<int,int> ;
using pll = pair<long long,long long>;
constexpr int INF = 1e9;
constexpr long long LINF = 1e17;
constexpr int MOD = 1000000007;
constexpr double PI = 3.14159265358979323846;

int main(){
    string s;
    cin >> s;
    int ans = INF;
    for(int i=0;i<(int)s.size();i++){
        for(int j=i+1;j<(int)s.size();j++){
            for(int k=j+1;k<(int)s.size();k++){
                if(s[i]=='c'&&s[j]=='w'&&s[k]=='w') ans = min(ans,k-i+1);
            }
        }
    }
    cout << (ans==INF?-1:ans) << endl;
    return 0;
}