#include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <math.h>
#include <cmath>
#include <limits.h>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <functional>
#include <stdio.h>
using namespace std;

long long MOD = 1000000007;

int main() {
    
    int ans = INT_MAX;
    string S;
    cin >> S;
    
    for ( int i = 0; i < S.length(); i++ ) {
    for ( int j = i+1; j < S.length(); j++ ) {
    for ( int k = j+1; k < S.length(); k++ ) {
        if ( S[i] == 'c' && S[j] == 'w' && S[k] == 'w' ) {
            ans = min( ans, k-i+1 );
        }
    }
    }
    }
    
    if ( ans == INT_MAX ) { cout << -1 << endl; }
    else { cout << ans << endl; }
    
    return 0;
}