import Foundation

final class FileIO {
    private let buffer:[UInt8]
    private var index: Int = 0

    init(fileHandle: FileHandle = FileHandle.standardInput) {
        
        buffer = Array(try! fileHandle.readToEnd()!) + [UInt8(0)]
    }

    @inline(__always) private func read() -> UInt8 {
        defer { index += 1 }
        return buffer[index]
    }

    @inline(__always) func readInt() -> Int {
        var sum = 0
        var now = read()
        var isPositive = true

        while now == 10 || now == 32 { now = read() }
        if now == 45 { isPositive = false; now = read() }

        while now >= 48, now <= 57 {
            sum = sum * 10 + Int(now-48)
            now = read()
        }

        return sum * (isPositive ? 1 : -1)
    }
}

let input = FileIO()
var ans: [String] = []

func solve() -> String {
    let (N, K) = (input.readInt(), input.readInt())
    
    var build_time: [Int] = [0]
    for _ in 0..<N {
        build_time.append(input.readInt())
    }
    
    var pre_build_info: [[Int]] = Array(repeating: [], count: N+1)
    for _ in 0..<K {
        let (X, Y) = (input.readInt(), input.readInt())
        pre_build_info[Y].append(X)
    }
    
    let W = input.readInt()
    
    var dp: [Int] = Array(repeating: -1, count: N+1)
    
    func build(_ n: Int) -> Int {
        if dp[n] == -1 {
            var total_time = 0
            for prev in pre_build_info[n] {
                total_time = max(total_time, build(prev))
            }
            dp[n] = total_time + build_time[n]
        }
        
        return dp[n]
    }
    
    return String(build(W))
}

func main() {
    let T = input.readInt()
    
    for _ in 0..<T {
        ans.append(solve())
    }
    
    print(ans.joined(separator: "\n"))
}

main()