import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner sc = new Scanner(System.in);
		String str = sc.next();
		char c1 = 'c';
		char c2 = 'w';
		int count = 0;
		int ans = -1;

		int i = 0;
		while(i < str.length()){
			if(str.charAt(i) == c1){
				int a = i;
				while(i < str.length()){
					if(str.charAt(i) == c2){
						count++;
						if(count == 2){
							ans = i + 1 - a;
							break;
						}
					}
					i++;
				}
				break;
			}
			i++;
		}
		System.out.println(ans);
	}
}