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#include <iostream>
#include <queue>
#include <vector>
using namespace std;

constexpr long long MOD = 1'000'000'007;

int inv(int x) {
    if (x <= 1) { return x; }
    return MOD - MOD / x * inv(MOD % x) % MOD;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;
    vector<int> bulbs, colors;
    vector<vector<int>> switches;
    bulbs.resize(n + 1);
    switches.resize(n + 1);
    colors.resize(n + 1);
    for (int i = 1; i <= n; ++i) {
        cin >> bulbs[i];
    }
    for (int i = 0; i < m; ++i) {
        int a, b;
        cin >> a >> b;
        switches[a].push_back(b);
        switches[b].push_back(a);
    }
    long long res = 1;
    for (int i = 1; i <= n; ++i) {
        if (colors[i] != 0) {
            continue;
        }
        long long allCount{}, oneCount{};
        bool oddCycle = false;
        colors[i] = 1;
        oneCount = bulbs[i] == 1;
        allCount = 1;
        queue<int> bfs;
        bfs.push(i);
        while (!bfs.empty()) {
            int bulb = bfs.front();
            bfs.pop();
            for (auto next : switches[bulb]) {
                if (colors[next] == colors[bulb]) {
                    oddCycle = true;
                }
                if (colors[next] != 0) continue;
                bfs.push(next);
                colors[next] = 3 - colors[bulb];
                ++allCount;

                oneCount += (colors[next] == 2) ^ (bulbs[next] == 1);
            }
        }
        long long roundRes = 1;
        if (oddCycle) {
            for (int k = 1; k < allCount; ++k) {
                roundRes *= 2;
                roundRes %= MOD;
            }
        } else {
            oneCount = min(oneCount, allCount - oneCount);
            for (int k = allCount; k > allCount - oneCount; --k) {
                roundRes *= k;
                roundRes %= MOD;
            }
            for (int k = 2; k <= oneCount; ++k) {
                roundRes *= inv(k);
                roundRes %= MOD;
            }
        }
        res *= roundRes;
        res %= MOD;
    }
    cout << res << '\n';
}