# Poj Solution 3256

```http://poj.org/problem?id=3256

//* @author: SmilingWang
import java.util.*;

public class Main {
static TreeSet< Integer> tmset = new TreeSet< Integer>();
static int[][] path;
static boolean[][] use;
static ArrayList[] table;
public static void main(String[] args){
Scanner in = new Scanner(System.in);
int k, m, n;
k = in.nextInt();
n = in.nextInt();
m = in.nextInt();
int g[] = new int[k];
for(int i = 0; i < k; i++){
g[i] = in.nextInt();
}
path = new int[n+1][n+1];
table = new ArrayList[n+1];
for(int i = 1; i <= n; i++){
path[i][i] = 1;
table[i] = new ArrayList< Integer>();
}
for(int i = 0; i < m; i++){
int a = in.nextInt();
int b = in.nextInt();
path[a][b] = 1;
}

for(int i = 0; i < k; i++){
use = new boolean[n+1][n+1];
search(g[i],n);
tmset.clear();
}
Iterator< Integer> iter = set.iterator();
int[] count= new int[n+1];
int   ncount = 0;
while(iter.hasNext()){
int tm = iter.next();
count[tm]++;
if(count[tm] >= k){
ncount++;
}
}
System.out.println(ncount);
}

public static void search(int start, int n){
for(int i = 0; i < table[start].size(); i++){
int j = (Integer)table[start].get(i);
if(path[start][j] > 0  && !use[start][j]){