#include "bits/stdc++.h"
//#include "atcoder/all"
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
using A = array<long long, 3>;
struct Edge {
	int to, cost;
	Edge(int to, int cost) :to(to), cost(cost) {}
};
int N, M;
vector<Edge>g[100005];
long long T[105];
long long d[101][1001];
long long dikstra() {
	rep(i, N) { rep(j, 1001) { d[i][j] = LINF; } }
	priority_queue<A, vector<A>, greater<A> > q;//小さいもの順
	q.push({ 0,0,0 });
	d[0][0] = 0;
	while (!q.empty()) {
		long long c = q.top()[0];
		long long v = q.top()[1];
		long long p = q.top()[2];
		q.pop();
		if (c > d[v][p]) { continue; }
		c += T[v];
		p = min(p + T[v], (long long)1000);
		for (Edge e : g[v]) {
			if (c + e.cost / p < d[e.to][p]) {
				d[e.to][p] = c + e.cost / p;
				q.push({ d[e.to][p],e.to,p });
			}
		}
	}
	long long ret = LINF;
	rep(i, 1001) {
		ret = min(ret, d[N - 1][i]);
	}
	return ret;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cin >> N >> M;
	rep(i, M) {
		int a, b, c;
		cin >> a >> b >> c;
		a--;
		b--;
		g[a].emplace_back(b, c);
		g[b].emplace_back(a, c);
	}
	rep(i, N) { cin >> T[i]; }
	cout << dikstra() << endl;
	return 0;
}