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#include <algorithm>
#include <iostream>
#include <ranges>
#include <unordered_map>
#include <set>
#include <vector>
#include <queue>

using namespace std;
using namespace std::views;

struct Edge {
    int end;
    int weight;
};

struct Signal {
    bool operator==(const Signal &) const = default;
    int x;
    int value;
};

struct SignalRange {
    int x;
    int s, e;
};

const long long threshold = 10000;

bool alreadyVisited(const set<pair<int, int>> &visited, pair<int, int> segment) {
    // return visited.contains(segment);
    auto it = visited.lower_bound(segment);
    if (it != visited.end() && it->first == segment.first) {
        return true;
    }
    if (it == visited.begin()) {
        return false;
    }
    --it;
    return it->second >= segment.second;
}

void addAlreadyVisited(set<pair<int, int>> &visited, pair<int, int> segment) {
    // visited.insert(segment); return;
    auto it = visited.lower_bound(segment);
    auto toDeleteStart = it;
    if (it != visited.begin()) {
        --it;
        if (it->second >= segment.first) {
            segment.first = it->first;
            segment.second = max(segment.second, it->first);
            toDeleteStart = it;
        }
        ++it;
    }
    while (it != visited.end() && it->first <= segment.second) {
        segment.second = max(segment.second, it->second);
        ++it;
    }
    visited.erase(toDeleteStart, it);
    visited.insert(segment);
}

bool exists(const vector<long long> &limits, unordered_map<int, vector<Edge>> &edgesRev, unordered_map<int, set<int>> &visited, int start, int end) {
    queue<SignalRange> bfs;
    bfs.push({(int)size(limits) - 1, start, end});
    unordered_map<int, set<pair<int, int>>> bfsVisited;
    bfsVisited[size(limits) - 1].insert({start, end});
    while (!bfs.empty()) {
        auto r = bfs.front();
        bfs.pop();
        auto it = visited[r.x].lower_bound(r.s);
        if (it != visited[r.x].end() && *it <= r.e) {
            return true;
        }
        for (const auto [e, w] : edgesRev[r.x]) {
            int newStart = (r.s + w - 1) / w, newEnd = min<int>(r.e / w, limits[e]);
            if (newStart <= newEnd && !alreadyVisited(bfsVisited[e], {newStart, newEnd})) {
                bfs.push({e, newStart, newEnd});
                addAlreadyVisited(bfsVisited[e], {newStart, newEnd});
            }
        }
    }
    return false;
}

long long binarySearch(const vector<long long> &limits, unordered_map<int, vector<Edge>> &edgesRev, unordered_map<int, set<int>> &visited) {
    long long start = 1, end = limits.back();
    if (!exists(limits, edgesRev, visited, start, end)) {
        return -1;
    }
    while (end - start > 0) {
        long long middle = (start + end + 1) / 2;
        if (exists(limits, edgesRev, visited, middle, end)) {
            start = middle;
        } else {
            end = middle - 1;
        }
    }
    return start;
}

void doOne() {
    int n, m;
    cin >> n >> m;
    vector<long long> limits;
    limits.resize(n + 1);

    for (int i : iota(1, n + 1)) {
        cin >> limits[i];
    }
    unordered_map<int, vector<Edge>> edges;
    unordered_map<int, vector<Edge>> edgesRev;
    for (int _ [[maybe_unused]] : iota(0, m)) {
        int a, b, w;
        cin >> a >> b >> w;
        if (a == b && w == 1) {
            continue;
        }
        edges[a].push_back({b, w});
        edgesRev[b].push_back({a, w});
    }
    for (auto &e : edges) {
        ranges::sort(e.second, [](Edge e1, Edge e2) {
            return e1.weight > e2.weight ? true : e1.weight < e2.weight ? false : e1.end < e2.end;
            });
    }
    for (auto &e : edgesRev) {
        ranges::sort(e.second, [](Edge e1, Edge e2) {
            return e1.weight > e2.weight ? true : e1.weight < e2.weight ? false : e1.end < e2.end;
            });
    }
    queue<Signal> bfs;
    unordered_map<int, set<int>> visited;
    bfs.push({1, 1});
    visited[1].insert(1);
    long long res = -1;
    while (!bfs.empty()) {
        auto p = bfs.front();
        bfs.pop();
        for (auto &[e, w] : edges[p.x]) {
            long long newSignal = (long long)p.value * w;
            if (newSignal <= threshold && newSignal <= limits[e] && !visited[e].contains(int(newSignal))) {
                bfs.push({e, int(newSignal)});
                visited[e].insert(newSignal);
                if (e == n && res < newSignal) {
                    res = newSignal;
                    if (res == limits[n]) {
                        cout << res << "\n";
                        return;
                    }
                }
            }
        }
    }

    res = binarySearch(limits, edgesRev, visited);

    cout << res << "\n";
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t;
    cin >> t;
    for (int _ [[maybe_unused]] : iota(0, t)) {
        doOne();
    }
}