import java.util.Arrays;
import java.util.Scanner;
 
public class Main {
    public static void main(String[] args) {
        try(Scanner sc = new Scanner(System.in)){
        	int n = sc.nextInt();
        	int [] S = new int[n];
        	for(int i=0;i<n;i++) {
        		S[i] = sc.nextInt();
        	}
        	
        	int q = sc.nextInt();
        	int [] T = new int[q];
        	for(int i=0;i<q;i++) {
        		T[i] = sc.nextInt();
        	}
        	int C = 0;
        	for(int i=0;i<q;i++) {
        		if(Arrays.binarySearch(S, T[i])>=0) {
        			C++;
        		}
        	}
        	System.out.println(C);
        }
    }
}
        		

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz