import java.util.*;
class A{
	static Scanner s = new Scanner(System.in);
	public static void main(String[] args) {
		String in = s.next().replaceAll("[^cw]", "");
		int w=0, r=0;
		for(int i=in.length()-1; i>=0; --i) {
			if(in.charAt(i)=='w') {
				w++;
			}else {
				r+=w*(w-1)/2;
			}
		}
		System.out.println(r);
	}
}