using System;
using System.Collections.Generic;
using System.Linq;

public class yukicoder
{
    public static void Main()
    {
        string s = Console.ReadLine();
        int c = s.IndexOf("w");
        int w = s.Length - c;

        if(c > w)
            Console.WriteLine(w);
        else
            Console.WriteLine(c - 1);
            
    }
}