import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.text.DecimalFormat;

public class HammouriandMountains
{
    public static void main(String[]args) throws Exception
    {
        BufferedReader b = new BufferedReader(new InputStreamReader(System.in));
//        BufferedReader b = new BufferedReader(new FileReader("Test"));
        char[]c = b.readLine().toCharArray();

        double sum = 0 , up = 0;
        for (int i = 0; i < c.length; i++)
        {
            if(c[i] == '/')
            {
                up++;
                sum += (up - 0.5);
            }
            else if(c[i] == '\\')
            {
                up--;
                sum += (up + 0.5);
            }
            else if(up > 0)
            {
                if(c[i] == '_')
                {
                    sum += up;
                }
            }
        }
        System.out.println(new DecimalFormat("#.#").format(sum));
    }
}