#include <stdio.h>

int main()
{
 int num = 0;
 int s[100000], t[50000];
 int ns, nt, i;

 scanf("%d", &ns);
 for ( i = 0; i < ns; ++i ){
   scanf("%d", &s[i]);
   for ( int j = 0; j < i; ++j ){
     if ( s[i] == s[j] ){
       s[i] = -1;
     }
   }
 }

 scanf("%d", &nt);
 for ( i = 0; i < nt; ++i ){
   scanf("%d", &t[i]);
   for ( int j = t[i] - 1; j < ns; ++j ){
     if ( t[i] == s[j] ){
       num++;
     }
   }
 }

 printf("%d\n", num);

 return 0;
}

