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

#define ll long long
#define pii pair<int, int>
#define MOD 1000000007ll

int state[200007];
vector<int> graph[200007];

bool has_neighbor(int v) {
    for (int u : graph[v]) {
        if (state[u] == state[v]) {
            return true;
        }
    }
    // cout << v << " does not have neighbor\n";
    return false;
}

bool dfs(int v, int col, vector<int>& vis, vector<ll>& size, vector<ll>& ones) {
    
    if (vis[v] != -1) {
        return (vis[v] == col);
    }
    // cout << v << "\n";

    vis[v] = col;
    size[col]++;
    ones[col] += state[v];

    col = (col + 1) % 2;
    bool bip = true;

    for (int u : graph[v]) {
        bip &= dfs(u, col, vis, size, ones);
    }
    return bip;
}

ll power(ll base, ll ind) {
    ll out = 1ll;
    while (ind > 0ll) {
        if (ind % 2ll == 1ll) {
            out *= base;
            out %= MOD;
        }
        ind /= 2ll;
        base *= base;
        base %= MOD;
    }
    return out;
}

ll fact[200007];

ll choose(ll n, ll k) {
    ll l = fact[n];
    ll m = (fact[n - k] * fact[k]) % MOD;
    ll out = (l * power(m, MOD - 2)) % MOD;
    // cout << n << " choose " << k <<" = " << out << "\n";
    return out;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    
    int n, m;
    cin >> n >> m;

    fact[0] = 1;
    for (ll i = 1; i <= (ll)(n); i++) {
        fact[i] = fact[i - 1] * i;
        fact[i] %= MOD;
    }

    for (int i = 1; i <= n; i++) {
        cin >> state[i];
    }

    for (int i = 0; i < m; i++) {
        int u, v;
        cin >> u >> v;
        graph[u].push_back(v);
        graph[v].push_back(u);
    }

    vector<int> vis(n + 1, -1);
    ll out = 1ll;

    for (int v = 1; v <= n; v++) {
        if (vis[v] == -1 && has_neighbor(v)) {
            // cout << "dfs from " << v << "\n";
            vector<ll> size(2, 0);
            vector<ll> ones(2, 0);
            bool bip = dfs(v, 1, vis, size, ones);

            if (!bip) { // 2 ^ size
                // cout << "not bipartite\n";
                out *= power(2ll, size[0] + size[1] - 1ll);
                out %= MOD;
            }
            else {
                // cout << "bipartite\n";
                // cout << size[0] << " " << size[1] << "\n";
                // cout << ones[0] << " " << ones[1] << "\n";

                ll diff = min(ones[0], ones[1]);
                ones[0] -= diff;
                ones[1] -= diff;

                // cout << ones[0] << " " << ones[1] << "\n";

                ll opt = 0;
                while (ones[0] <= size[0] && ones[1] <= size[1]) {
                    opt += (choose(size[0], ones[0]) * choose(size[1], ones[1]));
                    opt %= MOD; 
                    ones[0]++;
                    ones[1]++;
                }
                out *= opt;
                out %= MOD;
            }
        }
    }

    cout << out << "\n";
}