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

int n, m;
ll P = 1000000007;
std::vector<int> values;
std::vector<std::vector<int>> E;

std::vector<bool> visited;
std::vector<bool> bipartite_division;

void dfs(int x, int *bipartite_count, int *bipartite_sums, bool component, bool& not_bipartite) {
    visited[x] = true;
    bipartite_division[x] = component;
    bipartite_count[component]++;
    bipartite_sums[component] += values[x];
    for(int child : E[x]) {
        if(visited[child]) {
            if(bipartite_division[x] == bipartite_division[child]) {
                not_bipartite = true;
            }
            continue;
        }
        dfs(child, bipartite_count, bipartite_sums, !component, not_bipartite);
    }
}

ll fastexp(ll base, ll exp, ll mod) {
    if(exp == 0)
        return 1;
    if(exp % 2 == 0) {
        ll t = fastexp(base, exp / 2, mod);
        return (t * t) % mod;
    } else {
        return (base * fastexp(base, exp - 1, mod)) % mod;
    }
}

ll inverse_mod_prime(ll a, ll p) {
    return fastexp(a, p - 2, p);
}

ll factorials[500000];

void init() {
    factorials[0] = 1;
    for(ll i = 1; i < 500000; i++) {
        factorials[i] = (i * factorials[i - 1]) % P;
    }
}

ll binomial_coef_mod_P(int n, int k) {
    return factorials[n] * inverse_mod_prime(factorials[k], P) % P * inverse_mod_prime(factorials[n - k], P) % P;
}

int main() {
    init();
    cin >> n >> m;
    values = std::vector<int>(n + 1);
    visited = std::vector<bool>(n + 1, false);
    bipartite_division = std::vector<bool>(n + 1);
    for(int i = 1; i <= n; i++) {
        cin >> values[i];
    }
    E = std::vector<std::vector<int>>(n + 1);
    for(int i = 1; i <= m; i++) {
        int u, v;
        cin >> u >> v;
        E[u].push_back(v);
        E[v].push_back(u);
    }

    ll total = 1;
    for(int x = 1; x <= n; x++) {
        if(visited[x]) {
            continue;
        }
        int bipartite_count[2] = {0, 0};
        int bipartite_sums[2] = {0, 0};
        bool not_bipartite = false;
        dfs(x, bipartite_count, bipartite_sums, false, not_bipartite);
        if(not_bipartite) {
            ll component_size = bipartite_count[0] + bipartite_count[1];
            ll contribution = fastexp(2, component_size - 1, P);
            total = total * contribution % P;
            //std::cerr << "component of size " << bipartite_count[0] + bipartite_count[1] << "\n";
            //std::cerr << "contribution = " << contribution << "\n";
        } else {
            ll contribution = binomial_coef_mod_P(bipartite_count[0] + bipartite_count[1], bipartite_sums[0] - bipartite_sums[1] + bipartite_count[1]);
            total = total * contribution % P;
            //std::cerr << "bipartite component of size " << bipartite_count[0] << " " << bipartite_count[1]
            //    << ", sums " << bipartite_sums[0] << " " << bipartite_sums[1] << "\n";
            //std::cerr << "contribution = " << contribution << "\n";
        }
    }
    std::cout << total << "\n";
}