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#include <bits/stdc++.h>


using namespace std;


const int MOD = 1'000'000'007;
const int N = 200'004;


int fact[N], revFact[N];

vector <int> firstModRev(int n) {
    vector <int> rev(n + 1, 0);
    rev[1] = 1;

    for (int i = 2; i <= n; i++) {
        rev[i] = (-(long long) (MOD / i) * rev[MOD % i]) % MOD;

        if (rev[i] < 0) {
            rev[i] += MOD;
        }
    }

    return rev;
}

void prepareFact() {
    fact[0] = revFact[0] = 1;

    auto rev = firstModRev(N - 1);

    for (int i = 1; i < N; i++) {
        fact[i] = ((long long) i * fact[i - 1]) % MOD;
        revFact[i] = ((long long) rev[i] * revFact[i - 1]) % MOD;
    }
}

int binom(int n, int m) {
    if (n < m || m < 0) return 0;

    int res = ((long long) fact[n] * revFact[n - m]) % MOD;
    res = ((long long) res * revFact[m]) % MOD;

    return res;
}

int solve(int n, vector <int> &c, vector <vector<int>> &g) {
    int ans = 1;
    vector <int> par(n, -1);

    for (int v = 0; v < n; v++) if (par[v] == -1) {
        queue <int> q;
        q.push(v);

        par[v] = 0;

        bool bipartite = true;
        vector <int> verts;

        while (!q.empty()) {
            int u = q.front();
            q.pop();

            verts.push_back(u);

            for (int x : g[u]) {
                if (par[x] == -1) {
                    par[x] = 1 - par[u];
                    q.push(x);
                } else if (par[x] == par[u]) {
                    bipartite = false;
                }
            }
        }

        if (bipartite) {
            vector <int> numOnes(2, 0), numAll(2, 0);
            for (int v : verts) {
                numOnes[par[v]] += c[v];
                numAll[par[v]]++;
            }

            int diff = numOnes[1] - numOnes[0], total = 0;
            for (int i = 0; i <= numAll[0]; i++) {
                int j = i + diff;
                if (j >= 0 && j <= numAll[1]) {
                    total = (total + (long long) binom(numAll[0], i) * binom(numAll[1], j)) % MOD;
                }
            }

            ans = ((long long) ans * total) % MOD;
        } else {
            int pw = 1;
            for (int i = 1; i < verts.size(); i++) {
                pw *= 2;
                if (pw >= MOD) {
                    pw -= MOD;
                }
            }

            ans = ((long long) ans * pw) % MOD;
        }
    }

    return ans;
}

int main() {
    ios_base::sync_with_stdio(false);
    prepareFact();

    int n, m;
    cin >> n >> m;

    vector <int> c(n);
    for (int &ci : c) {
        cin >> ci;
    }

    vector <vector<int>> g(n);
    while (m--) {
        int u, v;
        cin >> u >> v; u--; v--;

        g[u].push_back(v);
        g[v].push_back(u);
    }

    cout << solve(n, c, g);

    return 0;
}