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#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned int ui;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<long long> vll;
const ll LINF = 1e18;
const int INF = 1e9;

ll dfs(ll node, vector<pii> &edges, vector<bool> &visited, int n) {
    if (visited[node]) {
        return 0;
    }
    visited[node] = true;
    // for (int i = 0; i < n; ++i) {
    //     cerr << ((node & (1L << i)) != 0);
    // }
    // cerr << endl;

    ll result = 1;
    for (size_t i = 0; i < edges.size(); ++i) {
        int a = edges[i].first;
        int b = edges[i].second;
        bool is_a_set = node & (1L << a);
        bool is_b_set = node & (1L << b);
        if (!(is_a_set ^ is_b_set)) {
            ll new_node = node ^ (1L << a) ^ (1L << b);
            result += dfs(new_node, edges, visited, n);
        }
    }
    return result;
}

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

    int n, m;
    cin >> n >> m;
    vector<bool> node(n);
    for (int i = 0; i < n; ++i) {
        int n_i;
        cin >> n_i;
        node[i] = n_i;
    }

    vector<pii> edges(m);
    for (int i = 0; i < m; ++i) {
        int a, b;
        cin >> a >> b;
        edges[i] = make_pair(a - 1, b - 1);
        // edges[a - 1].push_back(b - 1);
        // edges[b - 1].push_back(a - 1);
    }

    ll bitset = 0;
    for (int i = 0; i < n; ++i) {
        bitset |= (node[i] << i);
    }

    vector<bool> visited((1L << n));
    ll result = dfs(bitset, edges, visited, n);
    cout << result << endl;

    return 0;
}