#include <bits/stdc++.h>
//#include<boost/multiprecision/cpp_int.hpp>
//#include<boost/multiprecision/cpp_dec_float.hpp>
//#include <atcoder/all>
#define rep(i, a) for (int i = (int)0; i < (int)a; ++i)
#define rrep(i, a) for (int i = (int)a - 1; i >= 0; --i)
#define REP(i, a, b) for (int i = (int)a; i < (int)b; ++i)
#define RREP(i, a, b) for (int i = (int)a - 1; i >= b; --i)
#define repl(i, a) for (ll i = (ll)0; i < (ll)a; ++i)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define popcount __builtin_popcount
#define fi first
#define se second
using ll = long long;
constexpr ll mod = 1e9 + 7;
constexpr ll mod_998244353 = 998244353;
constexpr ll INF = 1LL << 60;

// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

//using lll=boost::multiprecision::cpp_int;
//using Double=boost::multiprecision::number<boost::multiprecision::cpp_dec_float<1024>>;//仮数部が1024桁
template <class T>
inline bool chmin(T &a, T b)
{
	if (a > b)
	{
		a = b;
		return true;
	}
	return false;
}
template <class T>
inline bool chmax(T &a, T b)
{
	if (a < b)
	{
		a = b;
		return true;
	}
	return false;
}

template <typename T>
T mypow(T x, T n, const T &p = -1)
{ //x^nをmodで割った余り

	if (p != -1)
	{
		x %= p;
	}
	T ret = 1;
	while (n > 0)
	{
		if (n & 1)
		{
			if (p != -1)
				ret = (ret * x) % p;
			else
				ret *= x;
		}
		if (p != -1)
			x = (x * x) % p;
		else
			x *= x;
		n >>= 1;
	}
	return ret;
}

using namespace std;
//using namespace atcoder;
struct edge{
	int to;
	ll cost;
	edge(int a,ll b):to(a),cost(b){}
};
vector<ll> dijkstra(const vector<vector<edge>> &g,int s){
	using P=pair<ll,int>;
	priority_queue<P,vector<P>,greater<>>pq;
	vector<ll>dis(g.size(),INF);
	pq.emplace(0,s);
	dis[s]=0;
	while(!pq.empty()){
		auto p=pq.top();
		pq.pop();
		ll d=p.first;
		int v=p.second;
		if(dis[v]<d)continue;
		for(auto x:g[v]){
			if(chmin(dis[x.to],dis[v]+x.cost)){
				pq.emplace(dis[x.to],x.to);
			}
		}
	}
	return dis;
}

void solve()
{	
	int n,m,p,q;
	ll t;
	cin>>n>>m>>p>>q>>t;
	p--;q--;
	vector<vector<edge>>g(n);
	rep(i,m){
		int a,b;
		ll c;
		cin>>a>>b>>c;
		a--;b--;
		g[a].eb(b,c);
		g[b].eb(a,c);
	}
	auto d=dijkstra(g,p);
	auto d2=dijkstra(g,q);
	auto d3=dijkstra(g,0);
	if(t<2*max(d[0],d2[0])){
		cout<<-1<<"\n";
		return;
	}
	ll ans=0;
	rep(i,n){
		rep(j,n){
			ll maxv=max(d[i]+d[j],d2[i]+d2[j])+d3[i]+d3[j];
			if(maxv<=t){
				chmax(ans,d3[i]+d3[j]+t-maxv);
				if(i==p||i==q){
					chmax(ans,t);
				}
			}
			
		}
	}
	cout<<ans<<"\n";
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout << fixed << setprecision(15);
	solve();
	return 0;
}