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#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;

#ifdef LOCAL
ostream &operator<<(ostream &out, string str)
{
    for (char c : str)
        out << c;
    return out;
}
template <class L, class R>
ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.first << ", " << p.second << ")"; }
template <class L, class R, class S>
ostream &operator<<(ostream &out, tuple<L, R, S> p)
{
    auto &[a, b, c] = p;
    return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T>
auto operator<<(ostream &out, T a) -> decltype(a.begin(), out)
{
    out << '{';
    for (auto it = a.begin(); it != a.end(); it = next(it))
        out << (it != a.begin() ? ", " : "") << *it;
    return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts>
void dump(T a, Ts... x)
{
    cerr << a << ", ";
    dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...) 42
#endif

vector<vi> G;
vi I, vis;
const ll MOD = 1'000'000'007;

bool bi(int v, int t)
{
    vis[v] = t;
    for (auto &u : G[v])
        if (vis[u] < 0)
        {
            if (!bi(u, 1 - t))
                return false;
        }
        else if (vis[u] == t)
            return false;
    return true;
}

void dfs2(int v, pii &ans, pii &sizes)
{
    if (vis[v])
    {
        sizes.first++;
        if (I[v])
            ans.first++;
    }
    else
    {
        sizes.second++;
        if (I[v])
            ans.second++;
    }
    vis[v] = 2;
    for (auto &a : G[v])
        if (vis[a] < 2)
            dfs2(a, ans, sizes);
}

void dfs(int v, int &ans)
{
    ans++;
    vis[v] = 3;
    for (auto &u : G[v])
        if (vis[u] < 3)
            dfs(u, ans);
}

ll pot(ll a, ll b)
{
    if (!b)
        return 1;
    if (b & 1)
        return (a * pot(a, b - 1)) % MOD;
    ll temp = pot(a, b / 2);
    return (temp * temp) % MOD;
}

ll fact(ll n)
{
    if (!n)
        return 1;
    return (n * fact(n - 1)) % MOD;
}

main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    int Z = 1;
    // cin >> Z;
    while (Z--)
    {
        int n, m;
        cin >> n >> m;
        G.resize(n);
        I.resize(n);
        vis.resize(n, -1);
        for (auto &a : I)
            cin >> a;
        while (m--)
        {
            int a, b;
            cin >> a >> b;
            --a;
            --b;
            G[a].push_back(b);
            G[b].push_back(a);
        }
        ll ans = 1;
        for (int i = 0; i < n; i++)
            if (vis[i] < 0)
            {
                bool dwu = bi(i, 0);
                int siz = 0;
                if (!dwu)
                {
                    dfs(i, siz);
                    ans = (ans * pot(2, siz - 1)) % MOD;
                }
                else
                {
                    pii cnt{0, 0}, num{0, 0};
                    dfs2(i, num, cnt);
                    if (num.first > num.second)
                    {
                        swap(num.first, num.second);
                        swap(cnt.first, cnt.second);
                    }
                    int dif = num.second - num.first;
                    ll sum = 0, cur = 1;
                    cur = (cur * fact(cnt.second)) % MOD;
                    cur = (cur * pot(fact(dif), MOD - 2)) % MOD;
                    cur = (cur * pot(fact(cnt.second - dif), MOD - 2)) % MOD;
                    sum = cur;
                    for (int i = 0; i + dif < cnt.second && i < cnt.first; i++)
                    {
                        cur = (cur * ll(max(1, cnt.first - i))) % MOD;
                        cur = (cur * ll(max(1, cnt.second - i - dif))) % MOD;
                        cur = (cur * pot(i + 1, MOD - 2)) % MOD;
                        cur = (cur * pot(i + dif + 1, MOD - 2)) % MOD;
                        sum = (sum + cur) % MOD;
                    }
                    ans = (ans * sum) % MOD;
                }
            }
        cout << ans << endl;
    }
}