#include <bits/stdc++.h>
using namespace std;

#define endl '\n'
#define int long long
#define ull unsigned long long
typedef long long ll;
#define lowbit(x) ((x) & -(x))

const ll INF = 0x3f3f3f3f;
const ll mod = 998244353;
const int N = 2e5 + 5, M = 5e5 + 10;
typedef pair<int, int> PII;
double T = 1 >> 30;
// double PI = acos(-1);

int gcd(int a, int b)
{
    return b ? gcd(b, a % b) : a;
}

int lcm(int a, int b)
{
    return a / gcd(a, b) * b;
}

struct edge
{
    int v, w;
};

vector<edge> e[N];

// void print_path(int s, int t)
// {
//     if (s == t)
//     {
//         printf("%d", s);
//         return;
//     }
//     print_path(s, pre[t]);
//     printf("->%d", t);
// }

struct node
{
    int id, dis;
    node(int a, int b)
    {
        id = a;
        dis = b;
    }

    bool operator<(const node &u) const
    {
        return dis > u.dis;
    }
};

int dist[N];
bool done[N];

void dij()
{
    for (int i = 0; i < N; i++)
    {
        dist[i] = INF;
        done[i] = 0;
    }

    dist[0] = 0;
    priority_queue<node> q;
    q.push({0, 0});

    while (!q.empty())
    {
        node u = q.top();
        q.pop();
        if (done[u.id])
            continue;
        done[u.id] = 1;
        for (int i = 0; i < e[u.id].size(); i++)
        {
            int v = e[u.id][i].v, w = e[u.id][i].w;
            if (done[v])
            {
                continue;
            }
            if (dist[v] > u.dis + w)
            {
                dist[v] = u.dis + w;
                q.push({v, dist[v]});
            }
        }
    }
}

void solve()
{
    int i, j;

    int n, m, l, r;
    cin >> n >> m >> l >> r;

    vector<PII> vec;
    while (m--)
    {
        int u, v, w;
        cin >> u >> v >> w;
        vec.push_back({u, v});
        e[u].push_back({v, w});
        e[v].push_back({u, w});
    }

    dij();
    int ans = 0;
    for (i = 0; i < vec.size(); i++)
    {
        int mn = min(dist[vec[i].first], dist[vec[i].second]);
        if (2 * mn < r)
        {
            ans++;
        }
    }

    cout << ans;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t = 1;

    // cin >> t;

    while (t--)
    {
        solve();
    }

  //  system("pause");
    return 0;
}