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/* 2025
 * Maciej Szeptuch
 */
#include <algorithm>
#include <cstdio>
#include <queue>
#include <unordered_set>
#include <vector>

int tests;
int verts;
int edges;

const int MAX_VERTS = 128;

std::vector<std::pair<int, int>> graph[MAX_VERTS];
std::vector<std::pair<int, int>> revgraph[MAX_VERTS];
int limit[MAX_VERTS];

void cleanup_limits(void);
int solve(void);

int main(void)
{
    scanf("%d", &tests);
    for(int t = 0; t < tests; ++t)
    {
        scanf("%d %d", &verts, &edges);
        for(int v = 0; v < verts; ++v)
        {
            scanf("%d", &limit[v]);
            graph[v].clear();
            revgraph[v].clear();
        }

        for(int e = 0; e < edges; ++e)
        {
            int start;
            int end;
            int amp;
            scanf("%d %d %d\n", &start, &end, &amp);
            --start;
            --end;
            graph[start].push_back({end, amp});
            revgraph[end].push_back({start, amp});
        }

        cleanup_limits();
        printf("%d\n", solve());
    }
    return 0;
}

void cleanup_limits(void)
{
    bool visited[128] = {};
    std::queue<int> que;
    que.push(verts - 1);
    visited[verts - 1] = true;
    while(!que.empty())
    {
        auto v = que.front();
        que.pop();

        for(const auto &[n, amp]: revgraph[v])
        {
            if(visited[n])
                continue;

            visited[n] = true;
            que.push(n);
        }
    }

    for(int v = 0; v < verts; ++v)
        if(!visited[v])
            limit[v] = 0;

    bool updated = false;
    do
    {
        updated = false;
        for(int v = 0; v < verts - 1; ++v)
        {
            if(!limit[v])
                continue;

            int max_limit = 0;
            for(const auto &[n, amp]: graph[v])
                max_limit = std::max(max_limit, limit[n] / amp);

            if(limit[v] > max_limit)
            {
                updated = true;
                limit[v] = max_limit;
            }
        }

        for(int v = 0; v < verts; ++v)
        {
            if(!limit[v])
                continue;

            long long int max_limit = 1;
            for(const auto &[n, amp]: revgraph[v])
                max_limit = std::max(max_limit, 1ll * limit[n] * amp);

            if(limit[v] > max_limit)
            {
                updated = true;
                limit[v] = max_limit;
            }
        }
    } while(updated);
}

template <>
struct std::hash<std::pair<int, int>>
{
    long long int operator()(const std::pair<int, int> &p) const
    {
        return ((1LL * p.first) << 32) + p.second;
    }
};

int solve(void)
{
    std::unordered_set<std::pair<int, int>> visited;
    std::priority_queue<std::pair<int, int>> que;
    int max_reached[MAX_VERTS] = {};
    visited.emplace(0, 1);
    que.push({1, 0});

    while(!que.empty() && max_reached[verts - 1] - 1 < limit[verts - 1])
    {
        const auto [signal, v] = que.top();
        que.pop();

        for(const auto &[n, amp]: graph[v])
        {
            long long int new_signal = 1ll * signal * amp;
            if(new_signal > limit[n])
                continue;

            if(visited.contains({n, new_signal}))
                continue;

            visited.emplace(n, new_signal);
            que.push({new_signal, n});
            max_reached[n] = std::max(1ll * max_reached[n], new_signal + 1);
        }
    }

    return max_reached[verts - 1] - 1;
}