package study;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

public class test2 {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String str1 = scanner.nextLine();
        String[] arr1=str1.split(" ");
        String str2 = scanner.nextLine();
        String[] arr2=str2.split(" ");
        String str = scanner.nextLine();
        String temp;
        Queue<String> queue = new LinkedList<String>();
        queue.offer(str);
        int n = 1;
        while(queue.size()>0) {
            temp = queue.poll();    
            for (int i = 0; i < arr2.length; i++) {
                if(temp.equals(arr2[i])) {
                    n=n+1;
                    queue.offer(arr1[i]);
                }
            }
        }

        System.out.println(n);
    }

}