#include <iostream>
#include <map>
#include <vector>
#include <queue>
#include <utility>
#define llint long long
#define inf 1e18

using namespace std;
typedef pair<llint, llint> P;

struct edge{
	llint to, cost;
	edge(){}
	edge(llint a, llint b){
		to = a, cost = b;
	}
};

llint n, m, p, q, t;
vector<edge> G[2005];
llint distS[2005], distP[2005], distQ[2005];

void dijkstra(llint S, llint dist[])
{
	for(int i = 1; i <= n; i++) dist[i] = inf;
	dist[S] = 0;
	
	priority_queue< P, vector<P>, greater<P> > Q;
	Q.push( make_pair(0, S) );
	
	llint v, d;
	while(Q.size()){
		d = Q.top().first;
		v = Q.top().second;
		Q.pop();
		if(dist[v] < d) continue;
		for(int i = 0; i < G[v].size(); i++){
			if(dist[G[v][i].to] > d + G[v][i].cost){
				dist[G[v][i].to] = d + G[v][i].cost;
				Q.push( make_pair(dist[G[v][i].to], G[v][i].to) );
			}
		}
	}
}

int main(void)
{
	cin >> n >> m >> p >> q >> t;
	llint u, v, w;
	for(int i = 1; i <= m; i++){
		cin >> u >> v >> w;
		G[u].push_back(edge(v, w));
		G[v].push_back(edge(u, w));
	}
	dijkstra(1, distS);
	dijkstra(p, distP);
	dijkstra(q, distQ);
	
	if(distS[p] + distP[q] + distQ[1] <= t){
		cout << t << endl;
		return 0;
	}
	
	llint ans = -1;
	for(int i = 1; i <= n; i++){
		for(int j = 1; j <= n; j++){
			llint spend = distS[i];
			spend += max(distP[i] + distP[j], distQ[i] + distQ[j]);
			spend += distS[j];
			if(spend > t) continue;
			ans = max(ans, t - max(distP[i] + distP[j], distQ[i] + distQ[j]));
		}
	}
	cout << ans << endl;
	
	return 0;
}