#include<iostream>
#include<vector>
#include<queue>
#include<utility>
using namespace std;
int main() {
  int N,K,M,P,u,v,x;
  cin >> N >> K >> M >> P;
  vector<vector<int>> G(N);
  while(M--) {
    cin >> u >> v;
    G[u-1].push_back(v-1);
    G[v-1].push_back(u-1);
  }
  vector<int> s(N);
  for(int i=0;i<N;i++)cin >> s[i];
  priority_queue<pair<long long,pair<int,int>>,vector<pair<long long,pair<int,int>>>,greater<pair<long long,pair<int,int>>>> q;
  while(K--) {
    cin >> x;
    q.push({0,{x-1,x-1}});
  }
  int ans = 0;
  vector<long long> t(N,-1),t2(N,1ll<<60);
  while(!q.empty()) {
    pair<long long,pair<int,int>> p = q.top();
    q.pop();
    if(p.first > t2[p.second.first])continue;
    if(t[p.second.second] < 0) {
      for(int i=0;i<G[p.second.second].size();i++) {
        q.push({p.first+s[p.second.second],{p.second.second,G[p.second.second][i]}});
      }
      t[p.second.second] = p.first;
    }
    else if(t[p.second.second] + P > p.first && t2[p.second.second] == 1ll<<60) {
      ans++;
      t2[p.second.second] = p.first;
    }
  }
  cout << ans << endl;
}