#include "bits/stdc++.h"
using namespace std;
     
#define DEBUG(x) cout<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cout<<#v<<":";for(int i=0;i<v.size();i++) cout<<" "<<v[i]; cout<<endl
     
typedef long long ll;
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
const int inf = 1000000001;
const ll INF = 1e16;
#define MOD 1000000007
#define mod 1000000009
#define pi 3.14159265358979323846
#define Sp(p) cout<<setprecision(15)<<fixed<<p<<endl;
int dx[4] = { 1,0,-1,0 }, dy[4] = { 0,1,0,-1 };
int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };

int main() {
  int i, j;
  string s;
  cin >> s;
  int ans = inf;
  for (i = 0; i < s.size(); i++) {
    if (s[i] == 'c') {
      int cnt = 0;
      for (j = i + 1; j < s.size(); j++) {
	if (s[j] == 'w') {
	  cnt++;
	}
	if (cnt == 2) {
	  ans = min(ans, j - i + 1);
	  break;
	}
      }
    }
  }
  if (ans == inf) {
    cout << -1 << endl;
  }else{
    cout << ans << endl;
  }
}