func main() {
    var ans: [Int] = []
    
    guard let T = Int(readLine() ?? "") else { return }
    
    for _ in 0..<T {
        guard let input1 = readLine() else { return }
        
        let NK = input1.split(separator: " ").compactMap{Int($0)}
        let (N, K) = (NK[0], NK[1])
        
        guard let input2 = readLine() else { return }
        let build_time: [Int] = [0] + input2.split(separator: " ").compactMap{Int($0)}
        
        var graph: [[Int]] = Array(repeating: [], count: N+1)
        var indegree: [Int] = Array(repeating: 0, count: N+1)
        
        for _ in 0..<K {
            guard let input3 = readLine(),
                  let XY = input3.split(separator: " ").compactMap({Int($0)}) as? [Int],
                  let X = XY.first, let Y = XY.last
            else { return }
            
            indegree[Y] += 1
            graph[X].append(Y)
        }
        
        guard let W: Int = Int(readLine() ?? "") else { return }
        
        var dp: [Int] = Array(repeating: 0, count: N+1)
        var qu: [Int] = Array(repeating: 0, count: N+1)
        var (front, rear) = (0, 0)
        
        for n in 1...N {
            if indegree[n] == 0 {
                qu[rear] = n
                rear += 1
                dp[n] = build_time[n]
            }
        }
        
        while front < rear {
            let now = qu[front]
            front += 1
            
            if now == W {
                break
            }
            
            for nxt in graph[now] {
                indegree[nxt] -= 1
                dp[nxt] = max(dp[nxt], dp[now] + build_time[nxt])
                if indegree[nxt] == 0 {
                    qu[rear] = nxt
                    rear += 1
                }
            }
        }
        
        ans.append(dp[W])
    }
    
    print(ans.map({String($0)}).joined(separator: "\n"))
}

main()