#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, k, m, p;
  cin >> n >> k >> m >> p;
  struct S {
    ll t;
    int u, v;
    bool operator<(const S& rhs) const {
      return t > rhs.t;
    }
  };
  priority_queue<S> evs;
  vector<char> removed(n);
  VL time(n, -1);
  VVI to(n);
  rep(_, m) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    to[u].emplace_back(v);
    to[v].emplace_back(u);
  }
  VI s(n);
  rep(i, n) cin >> s[i];
  auto infect = [&](int i, ll t) {
    time[i] = t;
    t += s[i];
    for(int j: to[i]) evs.push({t, i, j});
  };
  rep(_, k) {
    int x;
    cin >> x;
    x--;
    infect(x, 0);
  }
  while(evs.size()) {
    int t = evs.top().t;
    static vector<S> evs_today;
    evs_today.clear();
    while(evs.size() && evs.top().t == t) {
      evs_today.emplace_back(evs.top());
      evs.pop();
    }
    static VI to_remove;
    to_remove.clear();
    for(auto [_, u, v] : evs_today) {
      if (removed[u]) continue;
      if (time[v] == -1) {
        infect(v, t);
      } else if (t < time[v] + p) {
        to_remove.emplace_back(v);
      }
    }
    for(int v: to_remove) removed[v] = true;
  }
  int ans = accumulate(all(removed), 0);
  cout << ans << '\n';
}