#include <iostream>
#include <vector>

using namespace std;

int main()
{
  string s;
  getline( cin, s );

  const int INIT = 10000;
  int ans = INIT;
  
  for( int i = 0; i < s.size(); i++ )
  {
	if ( s[i] == 'c' )
	{
	  for( int j = i + 1; j < s.size(); j++ )
	  {
		if ( s[j] == 'w' )
		{
		  for( int k = j + 1; k < s.size(); k++ )
		  {
			if ( s[k] == 'w' )
			{
			  ans = min( ans, k - i + 1 );
			}
		  }
		}
	  }
	}
  }
  if ( ans == INIT )
  {
	cout << -1 << endl;
  }
  else
  {
	cout << ans << endl;
  }
}