#include <iostream>
#include <iomanip>
#include <cstdio>
#include <queue>
#include <cstring>
#include <vector>
#include <map>
#include <algorithm>
#include <cctype>
#include <cmath>
#include <bitset>
#include <set>
#include <deque>
#include <stack>
#include <atcoder/all>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define rrep(i,n) for(int i = 1; i <= (n); ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
#define srep(i,s,t) for (int i = s; i < (t); ++i)
#define dsrep(i,t,s) for(int i = (t)-1; i >= (s); --i)
#define rng(a) a.begin(),a.end()
#define rrng(a) a.rbegin(),a.rend()
#define isin(x,l,r) ((l) <= (x) && (x) < (r))
int dx4[4]={1,0,-1,0};
int dy4[4]={0,-1,0,1};
using ll = long long;
using uint = unsigned;
using ull = unsigned long long;
using P = pair<int,int>;
const ll LINF = 1001002003004005006ll;
const int INF = 1001001001;
const ll mod = 998244353;

////////////////////////////////////////////
int n, m, k;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  cin >> n >> m;
  vector<int> a(n);
  vector<P> ap;
  vector<bool> b(n, true);

  rep(i, n) {
    cin >> a[i];
    ap.push_back(P(a[i], i));
  }

  vector<int> g[n];
  rep(i, m) {
    int u, v;
    cin >> u >> v;
    u--; v--;
    g[u].push_back(v);
    g[v].push_back(u);
  }

  cin >> k;
  rep(i, k) {
    int t;
    cin >> t;
    t--;
    b[t] = false;
  }

  sort(ap.begin(), ap.end());
  vector<int> ans;
  rep(i, n) {
    int now = ap[i].second;
    if(b[now]) continue;

    ans.push_back(now + 1);
    for(auto x : g[now]) {
      if(a[x] > a[now]) {
        b[x] = !b[x];
      }
    }
  }

  cout << ans.size() << endl;
  for(auto x: ans) {
    cout << x << endl;
  }
}