using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace yukikoda
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = Console.ReadLine();
            int min = int.MaxValue;

            for (int i = 0; i < s.Length - 1; i++)
            {
                if (s[i] != 'c') continue;

                int cnt = 0;
                for (int j = i; j < s.Length ; j++)
                {
                    if (s[j] == 'w')
                    {
                        cnt++;
                    }

                    if (cnt == 2)
                    {
                        if (min > j - i)
                        {
                            min = j - i + 1;
                            break;
                        }
                    }
                }
            }

            if (min == int.MaxValue) min = -1;
            Console.WriteLine(min);
        }
    }
}