#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"
#define P pair<long long,pair<int,int>>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
struct Edge {
	int to, cost;
	Edge(int to, int cost) :to(to), cost(cost) {}
};
vector<Edge>g[105];
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n, m; 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);
	}
	vector<int>t(n);
	rep(i, n)cin >> t[i];
	vector dp(n, vector<long long>(1002, LINF));
	priority_queue<P, vector<P>, greater<P>> q;
	dp[0][t[0]] = t[0];
	q.push({ t[0],{0,t[0]} });
	while (!q.empty()) {
		auto top = q.top();
		q.pop();
		long long cost = top.first;
		int pos = top.second.first;
		int st = top.second.second;
		if (cost > dp[pos][st]) continue;
		for (auto e : g[pos]) {
			long long ncost = cost + e.cost / st + t[e.to];
			int npos = e.to;
			int nst = min(1001, st + t[e.to]);
			if (chmin(dp[npos][nst], ncost)) {
				q.push({ ncost,{npos,nst} });
			}
		}
	}
	long long ans = LINF;
	rep(i, 1001)chmin(ans, dp[n - 1][i]);
	cout << ans << endl;
	return 0;
}