#include <bits/stdc++.h> 
using namespace std;
using ll =long long;
#define all(v) v.begin(),v.end()
 #define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)

ll INF=2e18;


int main() {
    ios::sync_with_stdio(false);
  cin.tie(0);

ll N,K,M,P;cin>>N>>K>>M>>P;
vector<vector<ll>> vec(N,vector<ll> (0));
for(ll i=0;i<M;i++) {
  ll u,v;cin>>u>>v;
  u--;v--;
  vec[u].push_back(v);
  vec[v].push_back(u);
}

vector<ll> s(N);
for(ll i=0;i<N;i++) cin>>s[i];

priority_queue<pair<ll,ll>,vector<pair<ll,ll>>,greater<pair<ll,ll>>> S;

vector<ll> when(N,-1);
vector<ll> ken(N,INF);

ll ans=0;
for(ll i=0;i<K;i++) {
  ll x;cin>>x;
  x--;
  when[x]=0;
  S.push(make_pair(s[x],x));
}

while(!S.empty()) {
  auto v=S.top();
  S.pop();
  if(ken[v.second]<v.first) continue;
  
  for(auto x:vec[v.second]) {
     if(ken[x]!=INF) continue;
    if(when[x]!=-1&&when[x]+P<=v.first) continue;
     if(when[x]!=-1) {
      ken[x]=v.first;
      ans++;
    }
    else {
      when[x]=v.first;
      S.push(make_pair(s[x]+v.first,x));
    }
  }
}

cout<<ans<<endl;

}