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#include <algorithm>
#include <bitset>
#include <cstdio>
#include <limits>
#include <list>
#include <queue>
#include <set>
#include <vector>

using ull = unsigned long long;

typedef std::list<int> NodeList;
typedef std::set<int> NodeSet;

struct Node
{
	int index;
	unsigned distance;

	bool operator<(const Node& k) const {
		return distance < k.distance;
	}
};

struct Signal
{
	int index;
	unsigned volume;
};

unsigned mul(unsigned x, unsigned y) {
	ull z = static_cast<ull>(x) * static_cast<ull>(y);
	return std::min<ull>(z, std::numeric_limits<unsigned>::max());
}

int N, M;
std::set<int> W_forward[100];
std::set<int> W_reverse[100];

std::set<unsigned> amps[100][100];
std::set<unsigned> volumes[100];

std::vector<std::list<int>> cycles;
std::list<const std::list<int>*> cycle_pointers[100];

unsigned P[100];
unsigned D[100];

int policz() {
	std::priority_queue<Node> kandydaci;

	kandydaci.push({ N-1, 1 });
	D[N-1] = 1;
	std::fill(D, D+N-1, std::numeric_limits<unsigned>::max());
	while (!kandydaci.empty()) {
		Node k = kandydaci.top();
		kandydaci.pop();

		//printf("pętla dla #%d\n", k.index+1);
		for (const int out : W_reverse[k.index]) {
			//printf("próbujemy #%d #%d (%u)\n", k.index+1, w.out+1, w.amp);
			unsigned new_d = mul(k.distance, *amps[out][k.index].begin());
			if (new_d < D[out]) {
				D[out] = new_d;
				kandydaci.push({ out, new_d });
			}
		}
	}

	if (D[0] == std::numeric_limits<unsigned>::max()) {
		return -1; // nie ma żadnej ścieżki od początku do końca
	}
	for (int i=0; i<N; ++i) {
		if (D[i] != std::numeric_limits<unsigned>::max()) {
			//printf("ruter #%d dostał odległość %u\n", i+1, D[i]);
			P[i] = std::min(P[i], P[N-1] / D[i]);
			//printf("nowa przepustowość to %u\n", P[i]);
		}
	}

	bool changed = true;
	while (changed) {
		changed = false;
		for (int i=N-2; i>=0; --i) {
			unsigned max_out = 0;
			for (const int out : W_forward[i]) {
				max_out = std::max(max_out, P[out] / *amps[i][out].begin());
			}
			if (max_out < P[i]) {
				P[i] = max_out;
				changed = true;
			}
		}
	}

	if (P[0] == 0) {
		return -1;
	}
	std::queue<Signal> queue;
	volumes[0].insert(1);
	queue.push({0, 1});

	//fputs("START QUEUE", stderr);
	while (!queue.empty()) {
		Signal s = queue.front();
		queue.pop();
		//printf("#%d vol=%u\n", s.index+1, s.volume);

		for (const int out : W_forward[s.index]) {
			// można od razu określać max, a nie mnożyć po wszystkich
			// ale wcale nie działa szybciej!
			//unsigned max_amp = P[out] / s.volume;
			//auto it_after = amps[s.index][out].upper_bound(max_amp);
			for (unsigned amp : amps[s.index][out]) {
				unsigned amped = mul(s.volume, amp);
				if (amped <= P[out] && volumes[out].insert(amped).second) {
					queue.push({out, amped});
				}
			}
		}
	}
	//fputs("END QUEUE", stderr);
/*
	for (int i=0; i<N; ++i) {
		printf("VOLUMES #%d:\n", i+1);
		for (unsigned v : volumes[i]) {
			printf("%u\n", v);
		}
	}
*/
	return volumes[N-1].empty() ? -1 : static_cast<int>(*volumes[N-1].rbegin());
}

int main() {
	int T; scanf("%d", &T);
	while (T-- > 0) {
		scanf("%d%d", &N, &M);
		for (int i=0; i<N; ++i) {
			scanf("%u", &P[i]);
		}
		for (int j=0; j<M; ++j) {
			int in, out;
			unsigned amp;
			scanf("%d%d%u", &in, &out, &amp);
			if (in != out || amp > 1) {
				W_forward[in-1].insert(out-1);
				W_reverse[out-1].insert(in-1);
				amps[in-1][out-1].insert(amp);
			}
		}

		printf("%d\n", policz());
		if (T > 0) {
			for (int i=0; i<N; ++i) {
				for (int j : W_forward[i]) {
					amps[i][j].clear();
				}
				volumes[i].clear();
				W_forward[i].clear();
				W_reverse[i].clear();
				cycle_pointers[i].clear();
			}
			cycles.clear();
		}
	}
}