import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
     StringBuilder Zzz = new StringBuilder();
     Scanner in = new Scanner(System.in);
     String Stroka= in.nextLine();
     char b = in.next().charAt(0);
     boolean bl = false;
     for(int i =0;i<Stroka.length();i++) {
         if(Stroka.charAt(i)==b){
             System.out.println(i);
             bl = true;
             break;
         }
        }
        if (!bl) {
            System.out.println(-1);
        }

    }
}