#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define R cin>>
#define ll long long
#define ln cout<<'\n'
#define in(a) insert(a)
#define pb(a) push_back(a)
#define pd(a) printf("%.10f\n",a)
#define mem(a) memset(a,0,sizeof(a))
#define all(c) (c).begin(),(c).end()
#define iter(c) __typeof((c).begin())
#define rrep(i,n) for(ll i=(ll)(n)-1;i>=0;i--)
#define REP(i,m,n) for(ll i=(ll)(m);i<(ll)(n);i++)
#define rep(i,n) REP(i,0,n)
#define tr(it,c) for(iter(c) it=(c).begin();it!=(c).end();it++)
ll check(ll n,ll m,ll x,ll y){return x>=0&&x<n&&y>=0&&y<m;}void pr(){ln;}
template<class A,class...B>void pr(const A &a,const B&...b){cout<<a<<(sizeof...(b)?" ":"");pr(b...);}
template<class A>void PR(A a,ll n){rep(i,n)cout<<(i?" ":"")<<a[i];ln;}
const ll MAX=1e9+7,MAXL=1LL<<61,dx[8]={-1,0,1,0,-1,-1,1,1},dy[8]={0,1,0,-1,-1,1,1,-1};
typedef pair<ll,ll> P;

void Main() {
  ll n,m;
  cin >> n >> m;
  P p[n];
  ll a[n];
  rep(i,n) {
    cin >> a[i];
    p[i]=P(a[i],i);
  }
  vector<ll> v[n];
  rep(i,m) {
    ll x,y;
    cin >> x >> y;
    x--,y--;
    v[x].pb(y);
    v[y].pb(x);
  }
  ll u[n];
  mem(u);
  ll k;
  cin >> k;
  rep(i,k) {
    ll x;
    cin >> x;
    u[x-1]=1;
  }
  sort(p,p+n);
  vector<ll> ans;
  rep(i,n) {
    ll x=p[i].S;
    if(u[x]) {
      ans.pb(x+1);
      rep(i,v[x].size()) {
        ll y=v[x][i];
        if(a[x]<a[y]) u[y]^=1;
      }
    }
  }
  pr(ans.size());
  rep(i,ans.size()) pr(ans[i]);
}

int main(){ios::sync_with_stdio(0);cin.tie(0);Main();return 0;}