import java.util.*;

public class _1005_1 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int T = sc.nextInt();
        int[] ans = new int[T];

        for(int t=0; t<T; t++) {
            int N = sc.nextInt(), K = sc.nextInt();

            int[] build_time = new int[N+1];
            for(int i=1; i<=N; i++) build_time[i] = sc.nextInt();

            int[] indegree = new int[N+1];
            int[][] graph = new int[N+1][N+1];

            for(int i=0; i<K; i++) {
                int X = sc.nextInt(), Y = sc.nextInt();
                indegree[Y]++;
                graph[X][++graph[X][0]] = Y;
            }

            int W = sc.nextInt();
            int[] complete_time = new int[N+1];
            int[] qu = new int[N];
            int front = 0, rear = 0;
            for(int i=1; i<=N; i++) {
                if(indegree[i] == 0) {
                    qu[rear++] = i;
                    complete_time[i] = build_time[i];
                }
            }

            while(front <= rear) {
                int now = qu[front++];
                if(now == W) break;

                for(int i=1; i<=graph[now][0]; i++) {
                    int next = graph[now][i];
                    indegree[next]--;
                    complete_time[next] = Math.max(complete_time[now] + build_time[next], complete_time[next]);

                    if(indegree[next] == 0) {
                        qu[rear++] = next;
                    }
                }
            }

            ans[t] = complete_time[W];
        }
        
        sc.close();

        for (int n : ans) {
            System.out.println(n);
        }
    }
}