#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
using namespace std;

using ll = long long;
using P = pair<int, int>;
constexpr int INF = 1001001001;
constexpr int mod = 1000000007;
// constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m, p, q, t;
    cin >> n >> m >> p >> q >> t;
    --p, --q;
    vector<vector<P>> graph(n);
    for(int i = 0; i < m; ++i){
        int a, b, c;
        cin >> a >> b >> c;
        --a, --b;
        graph[a].emplace_back(b, c);
        graph[b].emplace_back(a, c);
    }
    
    constexpr ll inf = 1e+17;
    auto dijkstra = [&](int s){
        vector<ll> dist(n, inf);
        dist[s] = 0;
        using Data = pair<ll, int>;
        priority_queue<Data, vector<Data>, greater<Data>> que;
        que.emplace(0, s);
        while(!que.empty()){
            auto [d, from] = que.top();
            que.pop();
            if(d > dist[from])  continue;
            for(auto [to, cost] : graph[from]){
                if(chmin(dist[to], dist[from] + cost)){
                    que.emplace(dist[to], to);
                }
            }
        }
        return dist;
    };

    auto dist1 = dijkstra(0);
    auto distp = dijkstra(p);
    auto distq = dijkstra(q);

    if(dist1[p] + distp[0] + dist1[q] + distq[0] <= t){
        cout << t << endl;
        return 0;
    }
    if(dist1[p] + distp[q] + distq[0] <= t){
        cout << t << endl;
        return 0;
    }
    if(dist1[q] + distq[p] + distp[0] <= t){
        cout << t << endl;
        return 0;
    }
    
    ll ans = -1;
    for(int i = 0; i < n; ++i){
        for(int j = 0; j < n; ++j){
            ll max_dist = max(distp[i] + distp[j], distq[i] + distq[j]);
            if(dist1[i] + max_dist + dist1[j] <= t){
                chmax(ans, t - max_dist);
            }
        }
    }
    cout << ans << endl;

    return 0;
}