/*
import java.io.IOException;
import java.io.InputStream;
import java.util.NoSuchElementException;
*/
import java.io.IOException;
import java.io.InputStream;
import java.util.InputMismatchException;

public class Main {
	static int[] boo = new int[100000];
	public static void main(String[] args)throws Exception{
	//	 FastScanner sc = new FastScanner();
		 InputReader sc = new InputReader(System.in);
		
		int n = (sc.nextInt());
		//String[] st = br.readLine().split(" ");
		//boolean[] boo = new boolean[100000];
		
		for (int i = 0; i < n; i++) {
			//boo[Integer.parseInt(st[i])%100000] = 1;
			boo[sc.nextInt()%100000] = 1;
		}
		
		int ans = 0;
		//n = Integer.parseInt(br.readLine());
		n = sc.nextInt();
		//st = br.readLine().split(" ");
		for (int i = 0; i < n; i++) {
//			ans += boo[Integer.parseInt(st[i])%100000] ;
			ans += boo[sc.nextInt()%100000] ;
		}
		System.out.println(ans);
	}
	
	static class InputReader {
	      private InputStream stream;
	      private byte[] buf = new byte[1024];
	      private int curChar;
	      private int numChars;
	      private SpaceCharFilter filter;
	 
	      public InputReader(InputStream stream) {
	          this.stream = stream;
	      }
	  
	      public int next() {
	          if (numChars == -1)
	              throw new InputMismatchException();
	          if (curChar >= numChars) {
	              curChar = 0;
	              try {
	                  numChars = stream.read(buf);
	              } catch (IOException e) {
	                  throw new InputMismatchException();
	              }
	              if (numChars <= 0)
	                  return -1;
	          }
	          return buf[curChar++];
	      }
	  
	      public String nextStr() {
	        int c = next();
	        while(isSpaceChar(c)){c = next();}
	        StringBuffer str = new StringBuffer();
	        do{
	          str.append((char)c);
	          c = next();
	        }while(!isSpaceChar(c));
	        return str.toString();
	      }
	 
	      public int nextInt() {
	          int c = next();
	          while (isSpaceChar(c))
	              c = next();
	          int sgn = 1;
	          if (c == '-') {
	              sgn = -1;
	              c = next();
	          }
	          int res = 0;
	          do {
	              if (c < '0' || c > '9')
	                  throw new InputMismatchException();
	              res *= 10;
	              res += c - '0';
	              c = next();
	          } while (!isSpaceChar(c));
	          return res * sgn;
	      }
	  
	      public boolean isSpaceChar(int c) {
	          if (filter != null)
	              return filter.isSpaceChar(c);
	          return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	      }
	  
	      public interface SpaceCharFilter {
	          public boolean isSpaceChar(int ch);
	      }
	  }

	
}
/*
class FastScanner {
    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        }else{
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }
    private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
    private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
    public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
    public String next() {
        if (!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while(isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }
    public long nextLong() {
        if (!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while(true){
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            }else if(b == -1 || !isPrintableChar(b)){
                return minus ? -n : n;
            }else{
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    public int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
        return (int) nl;
    }
    public double nextDouble() { return Double.parseDouble(next());}
}*/

Measured memory_bytes: 26436