// #define DEBUGGING
#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define ALL(V) (V).begin(), (V).end()
#define ALLR(V) (V).rbegin(), (V).rend()

template <typename T> using V = vector<T>;
template <typename T> using VV = V<V<T>>;
using ll = int64_t;
using ull = uint64_t;
using PLL = pair<ll, ll>;

template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return max(low, min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { t = clamp(t, low, high); }

namespace init__ {

struct InitIO {
    InitIO() {
        cin.tie(nullptr);
        ios_base::sync_with_stdio(false);
        cout << fixed << setprecision(30);
    }
} init_io;

}

#ifdef DEBUGGING
#include "../debug.cpp"
#else
#define DEBUG(...) 0
#define DEBUG_SEPARATOR_LINE 0
#endif

template <typename T>
T make_v(T init) { return init; }

template <typename T, typename... Tail>
auto make_v(T init, size_t s, Tail... tail) {
#define rec make_v(init, tail...)
    return V<decltype(rec)>(s, rec);
#undef rec
}

VV<PLL> edges;
const ll inf = 5e15;
ll N, M, P, Q, T;
using PQ = priority_queue<PLL, V<PLL>, greater<PLL>>;

V<ll> dijk(ll start) {
    V<ll> dists(N, inf);
    dists[start] = 0;
    PQ pq;
    pq.emplace(0, start);
    while(pq.size()) {
        ll dist, now;
        tie(dist, now) = pq.top();
        pq.pop();
        if(dists[now] < dist) continue;
        for(const auto &edge : edges[now]) {
            ll nxt, cost;
            tie(nxt, cost) = edge;
            if(dists[nxt] <= dist + cost) continue;
            dists[nxt] = dist + cost;
            pq.emplace(dist + cost, nxt);
        }
    }
    return dists;
}

int main() {
    cin >> N >> M >> P >> Q >> T;
    P--; Q--;
    edges.resize(N);
    for(ll i = 0; i < M; i++) {
        ll a, b, c;
        cin >> a >> b >> c;
        a--; b--;
        edges[a].emplace_back(b, c);
        edges[b].emplace_back(a, c);
    }

    auto dists_start = dijk(0);
    auto dists_p = dijk(P);
    auto dists_q = dijk(Q);

    if(dists_start[P] + dists_p[Q] + dists_q[0] <= T) {
        cout << T << endl;
        return 0;
    }

    ll ans = -1;
    for(ll i = 0; i < N; i++) for(ll j = 0; j < N; j++) {
        ll same_first = dists_start[i];
        ll pass_p = dists_p[i] + dists_p[j];
        ll pass_q = dists_q[i] + dists_q[j];
        ll same_last = dists_start[j];
        ll sum = same_first + max(pass_p, pass_q) + same_last;
        if(sum <= T) chmax(ans, T - max(pass_p, pass_q));
    }
    cout << ans << endl;
    return 0;
}