#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> veci;
typedef vector<ll> vecll;
#define fi first
#define se second
#define vec vector
#define pq priority_queue
int main() {
ios_base::sync_with_stdio(false); cin.tie(0);
ll n, m;
cin >> n >> m;
ll s, t, l, k;
cin >> s >> t >> l >> k;
s--; t--;
vec<pll> adj[n];
while (m--) {
ll x, y, c;
cin >> x >> y >> c;
x--; y--;
adj[x].push_back({y, c});
adj[y].push_back({x, c});
}
ll ans=0;
for (ll i1=0; i1<n; i1++) {
for (ll j1=i1+1; j1<n; j1++) {
adj[j1].push_back({i1, l});
adj[i1].push_back({j1, l});
ll dist[n];
priority_queue<pll,vector<pll>,greater<pll>> q;
//change 2nd val for changing start
q.push(pll(0,s));
for (int i = 0; i < n; i++){
dist[i] = LLONG_MAX;
}// |
// V change this val for changing start
dist[s] = 0;
while (!q.empty()){
pll p = q.top();
q.pop();
ll d = p.first, u = p.second;
if (d > dist[u]) continue;
for (ll i = 0; i < (adj[u]).size(); i++){
ll nu = adj[u][i].first,w = adj[u][i].second;
if (dist[nu] > dist[u] + w){
dist[nu] = dist[u] + w;
q.push(pll(dist[nu],nu));
}
}
}
ans += (dist[t]<=k);
adj[j1].pop_back();
adj[i1].pop_back();
}
}
cout << ans;
return 0;
}
