import java.util.*;

public class Main {
	static Scanner sc = new Scanner(System.in);
	public static void main(String[] args) {
		String s = sc.next();
		String status = "";
		int min = 1000;
		int len = 0;
		int j = 0;
		for (int i=0; i<s.length(); i++) {
			char c = s.charAt(i);
			if (c!='c') {continue;}
			
			int t = 0;
			for (j=i+1; j<s.length(); j++) {
				if (s.charAt(j)=='w') {t++;}
				if (t == 2) {break;}
			}
			if (t == 2) {
				j = j-i+1;
				min = Math.min(min,j);
			}
		}
		System.out.println(min==1000?-1:min);
	}
}