#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cctype>
#include<cstdlib>
#include<algorithm>
#include<bitset>
#include<cstdio>
#include<cstring>
#include<string>
#include<cctype>
#include<cstdlib>
#include<algorithm>
#include<bitset>
#include<vector>
#include<list>
#include<deque>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<cmath>
#include<sstream>
#include<fstream>
#include<iomanip>
#include<ctime>
#include<complex>
#include<functional>
#include<climits>
#include<cassert>
#include<iterator>
using namespace std;

string s;


string f = "cww";
int main(){
	cin >> s;
	int maxt = INT_MAX;
	for (int i = 0; i < s.size(); i++){
		int ind = 0;
		for (int j = i; j < s.size(); j++){
			if (s[j] == f[ind]){
				ind++;
				if (ind == 3){
					maxt = min(maxt, j - i + 1);
					break;
				}
				
			}
		}
	}
	if (maxt == INT_MAX){
		maxt = -1;
	}
	cout << maxt << endl;
	return 0;
}