#include <stdio.h>#include <stdlib.h>#include <string.h>#define nMax 1005int cow[105];bool map[nMax][nMax];bool flag[nMax];int K,N;int pastures[nMax];void dfs(int now){flag[now] = true;pastures[now] ++;for (int i = 1; i <= N; ++ i){if (!flag[i] && map[now][i]){dfs(i);}}}int main(){int M;while(scanf("%d %d %d", &K, &N, &M) != EOF){memset(map, false, sizeof(map));memset(pastures, 0, sizeof(pastures));//多少牛能到此牧草地for (int i = 1; i <= K; ++ i){scanf("%d", &cow[i]);//第i头牛所在的牧草地}int u,v;for (int i = 0; i < M; ++ i){scanf("%d %d", &u, &v);map[u][v] = true;//牧草地u到v有路}for (int i = 1; i <= K; ++ i){memset(flag, false, sizeof(flag));//每次dfs是否走过idfs(cow[i]);}int cnt = 0;for (int i = 1; i <= N; ++ i){if (pastures[i] == K)//如果牧草地K头牛都能到，则++{cnt ++;}}printf("%dn", cnt);}return 0;}
