export {};
const input = require("fs").readFileSync(0).toString().trim().split("\n");
const T: number = Number(input[0]);
let idx: number = 1;

let res: number[] = [];

for(let t=0; t<T; t++) {
    const [N, K]: number[] = input[idx++].split(" ").map(Number);
    const line1: number[] = input[idx++].split(" ").map(Number);
    const build_time: number[] = Array.from({length: N+1}, (_,i) => i===0 ? 0 : line1[i-1]);

    let indegree: number[] = new Array(N+1).fill(0);
    let graph: number[][] = Array.from({length: N+1}, () => []);
    for(let k=0; k<K; k++) {
        const [X, Y]: number[] = input[idx++].split(" ").map(Number);
        indegree[Y]++;
        graph[X].push(Y);
    }

    const W: number = Number(input[idx++]);

    let qu: number[] = new Array(N).fill(0);
    let [front, rear]: number[] = [0,0];
    let dp: number[] = new Array(N+1).fill(0);
    for(let i=1; i<=N; i++) {
        if(indegree[i] === 0) {
            qu[rear++] = i;
            dp[i] = build_time[i];
        }
    }

    while(front < rear) {
        const now: number = qu[front++];

        if(now === W) break;

        for(let next of graph[now]) {
            indegree[next]--;
            dp[next] = Math.max(dp[next], dp[now] + build_time[next]);
            if(indegree[next]===0) {
                qu[rear++] = next;
            }
        }
    }

    res.push(dp[W]);
}

console.log(res.join("\n"));