#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
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; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	int N, M, P, Q, T;
	cin >> N >> M >> P >> Q >> T;
	--P; --Q;
	vector<vector<pii>> g(N);
	REP(i, M) {
		int a, b, c;
		scanf("%d %d %d", &a, &b, &c);
		--a; --b;
		g[a].emplace_back(b, c);
		g[b].emplace_back(a, c);
	}
	
	auto dijkstra = [&](int s) {
		vector<ll> dist(N, longINF);
		using P = pair<ll, int>;
		priority_queue<P, vector<P>, greater<P>> pq;
		dist[s] = 0;
		pq.emplace(0, s);
		while (!pq.empty()) {
			auto [d, u] = pq.top();
			pq.pop();
			if (dist[u] != d) continue;
			for (auto [v, t] : g[u]) if (chmin(dist[v], d + t)) pq.emplace(dist[v], v);
		}
		return dist;
	};
	
	auto dist1 = dijkstra(0), distp = dijkstra(P), distq = dijkstra(Q);
	if (dist1[P] + distp[Q] + distq[0] <= T) { cout << T << endl; return 0; }
	if (2 * dist1[P] > T || 2 * dist1[Q] > T) { puts("-1"); return 0; }
	
	ll ans = 0;
	REP(i, N) REP(j, N) {
		ll a = dist1[i] + distp[i] + distp[j];
		ll b = dist1[i] + distq[i] + distq[j];
		ll t = max(a, b) + dist1[j];
		if (t <= T) chmax(ans, dist1[i] + dist1[j] + T - t);
	}
	cout << ans << endl;
}