import java.util.*;

public class Main {
    public static void main(String args[]) {
        Scanner scan = new Scanner(System.in);
        String line;
        while (scan.hasNextLine()) {
            line = scan.nextLine();
            // please write your code here

            System.out.println(Main.solution(line));
        }
    }
    private static String solution(String line){
        String [] str=line.split(" ");///以空格分离的两个字符串4,5,6,7,0,1,2 6
        String [] str1=str[0].split(",");///以逗号分离的字符串4,5,6,7,0,1,2
        String goal = str[1];
        for(int i=0;i<str1.length;i++)
            if(str1[i].equals(goal)) return String.valueOf(i);

        return String.valueOf(-1);
    }
}