#include <algorithm>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <iostream>
#include <map>
#include <memory>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
 
using namespace std;
 
#define sz size()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(c) (c).begin(), (c).end()
#define rep(i,a,b) for(int i=(a);i<(b);++i)
#define clr(a, b) memset((a), (b) ,sizeof(a))
 
#define MOD 1000000007

int main(){
  string s;
  cin>>s;
  int mn = 1000;
  rep(i,0,s.sz){
    rep(j,i+1,s.sz){
      if(s[i]=='c'&&s[j]=='w'){
        int flag = 0;
        rep(k,i+1,j){
          if(s[k]=='w')flag=1;
        }
        if(flag==1){
          mn = min(mn,j-i+1);
        }
      }
    }
  }
  if(mn==1000){
    cout << -1 << endl;
    return 0;
  }
  cout << mn << endl;
  return 0;
}