#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
int a[100010], b[100010], in[100010];
vector<pair<int, int>> vec;
vector<vector<int>> v(100010);
vector<int> ans;
bool bo[100010] = { false };
int main() {
	int n, m;
	cin >> n >> m;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		vec.emplace_back(make_pair(a[i], i));
	}
	sort(vec.begin(), vec.end());
	for (int i = 1; i <= n; i++) {
		in[i] = vec[i - 1].second;
	}
	for (int i = 0; i < m; i++) {
		int c, d;
		cin >> c >> d;
		v[c].emplace_back(d);
		v[d].emplace_back(c);
	}
	int k;
	cin >> k;
	for (int i = 0; i < k; i++) {
		int b1;
		cin >> b1;
		bo[b1] = true;
	}
	for (int i = 1; i <= n; i++) {
		if (bo[in[i]]) {
			bo[in[i]] = false;
			for (int j = 0; j < v[in[i]].size(); j++) {
				if (a[in[i]] < a[v[in[i]][j]]) {
					bo[v[in[i]][j]] = !bo[v[in[i]][j]];
				}
			}
			ans.emplace_back(in[i]);
		}
	}
	cout << ans.size() << endl;
	for (int i = 0; i < ans.size(); i++) {
		cout << ans[i] << endl;
	}
}