import java.util.HashMap; import java.util.Scanner; public class Main2 { public static void main(String[] args){ Scanner reader = new Scanner(System.in); int n = reader.nextInt(); reader.nextLine(); String[] go = reader.nextLine().split(" "); String[] arrive = reader.nextLine().split(" "); HashMap<Integer,Integer> arrivedMap = new HashMap<>(); for(int i = 0; i < n;i++){ arrivedMap.put(Integer.parseInt(arrive[i]),i); } // 每一个数字之前出发的人最大到达index int[] dpmax = new int[n]; int count = 0; dpmax[0] = Integer.MIN_VALUE; for(int i = 1; i < n;i++){ dpmax[i] = Math.max(dpmax[i - 1],arrivedMap.get(Integer.parseInt(go[i - 1]))); if(dpmax[i] > arrivedMap.get(Integer.parseInt(go[i]))){ count++; } } System.out.println(count); } }