#include<bits/stdc++.h>
//#include"atcoder/all"
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#define all(a) (a).begin(),(a).end()
using namespace std;
//using namespace atcoder;
int main(){
  string s;cin >> s;
  int n=s.size(),i,j,k,ans = 10000;
  for(i=0;i<n-2;i++){
    for(j=i+1;j<n-1;j++){
      for(k=j+1;k<n;k++){
        if(s[i] == 'c' && s[j] == 'w' && s[k] == 'w') ans = min(ans,k-i+1);
      }
    }
  }
  if(ans == 10000) printf("-1\n");
  else printf("%d\n",ans);
}