#include <iostream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <list>
#include <iterator>
#include <cassert>
#include <numeric>
#include <functional>
#include <ctime>
#pragma warning(disable:4996) 

//#define ATCODER
#ifdef ATCODER
#include <atcoder/all>
#endif

typedef long long ll;
typedef unsigned long long ull;
#define LINF  9223300000000000000
#define LINF2 1223300000000000000
#define LINF3 1000000000000
#define INF 2140000000
//const long long MOD = 1000000007;
const long long MOD = 998244353;

using namespace std;
#ifdef ATCODER
using namespace atcoder;
#endif

void solve()
{
    int n, m;
    scanf("%d%d", &n, &m);
    vector<int> a(n);
    vector<vector<int>> g(n);   // to
    vector<pair<int, int>> z;   // a[i],i
    int i;
    for (i = 0; i < n; i++) {
        scanf("%d", &a[i]);
        z.push_back(make_pair(a[i], i));
    }
    sort(z.begin(), z.end());

    for (i = 0; i < m; i++) {
        int u, v;
        scanf("%d%d", &u, &v); u--; v--;
        if (a[u] < a[v]) g[u].push_back(v);
        else if (a[u] > a[v]) g[v].push_back(u);
    }

    vector<int> x(n);
    int K;
    scanf("%d", &K);
    for (i = 0; i < K; i++) {
        int tmp;
        scanf("%d", &tmp); tmp--;
        x[tmp] = 1;
    }

    vector<int> ans;
    for (i = 0; i < n; i++) {
        int id = z[i].second;
        if (x[id]) {
            ans.push_back(id);
            int j;
            for (j = 0; j < (int)g[id].size(); j++) {
                x[g[id][j]] = 1 - x[g[id][j]];
            }
        }
    }
    printf("%d\n", (int)ans.size());
    for (i = 0; i < (int)ans.size(); i++) {
        printf("%d\n", ans[i] + 1);
    }

    return;
}


int main()
{
#if 1
    solve();
#else
    int T, t;
    scanf("%d", &T);
    for (t = 0; t < T; t++) {
        //printf("Case #%d: ", t + 1);
        solve();
    }
#endif
    return 0;
}