#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
template<class T> void check_min(T &a, const T &b){ a = (a < b) ? a : b; }
template<class T> void check_max(T &a, const T &b){ a = (a > b) ? a : b; }
#define all(x) (x).begin(), (x).end()

const ll INF = 1e18 + 3;

void dijkstra(int start, int c_idx, int n, int m, vector<vector<array<ll, 3>>> &adj, vector<ll> &d){
    priority_queue<array<ll, 2>, vector<array<ll, 2>>, greater<array<ll, 2>>> pq;

    fill(d.begin(), d.end(), INF);
    d[start] = 0;
    pq.push({0, start});

    while(!pq.empty()){
        auto [du, u] = pq.top();
        pq.pop();

        if(du > d[u]) continue;

        for(auto edge: adj[u]){
            int to = edge[0];
            ll cost = edge[c_idx];

            ll cand = du + cost;
            if(cand < d[to]){
                d[to] = cand;
                pq.push({d[to], to});
            }
        }
    }
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    freopen("hurry.in", "r", stdin);
    freopen("hurry.out", "w", stdout);

    int t;
    cin >> t;

    while(t--){
        int n, m;
        cin >> n >> m;

        vector<vector<array<ll, 3>>> adj(n + 1);
        for(int i = 0; i < m; ++i){
            int u, v, a, b;
            cin >> u >> v >> a >> b;
            adj[u].push_back({v, a, b});
            adj[v].push_back({u, a, b});
        }

        vector<ll> d[2];
        for(int i = 0; i < 2; ++i)
            d[i].resize(n + 1);
        dijkstra(1, 1, n, m, adj, d[0]);
        dijkstra(n, 2, n, m, adj, d[1]);

        ll ans = INF;
        for(int i = 1; i <= n; ++i)
            check_min(ans, d[0][i] + d[1][i]);
        cout << ans << "\n";
    }
}