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//GRT_2018
#include <bits/stdc++.h>
#define PB push_back
#define ST first
#define ND second
#define all(x) x.begin(), x.end()
//mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

using namespace std;

using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;

const int mod = 1e9 + 7, nax = 200 * 1000 + 10;
int n, m;
int c[nax];
int fact[nax], inv[nax];
bool col[nax];

int bi(int a, int b) {
    ll me = ((ll)fact[a] * inv[b]) % mod;
    me = (me * inv[a - b]) % mod;
    return me;
}

int fastpow(int a, int b) {
    int w = 1;
    while (b) {
        if (b & 1) w = ((ll)w * a) % mod;
        b >>= 1;
        a = ((ll)a * a) % mod;
    }
    return w;
}

vi V[nax];
bool vis[nax];
int o1, o2, sz1, sz2;
bool odd;

void dfs(int x) {
    vis[x] = true;
    if (col[x]) {
        o1 += (c[x] == 1);
        sz1++;
    } else {
        o2 += (c[x] == 1);
        sz2++;
    }
    for (int y : V[x]) {
        if (!vis[y]) {
            col[y] = 1 - col[x];
            dfs(y);
        } else if (col[y] == col[x]) odd = true;
    }
}
int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
    cin >> n >> m;
    fact[0] = 1;
    inv[0] = 1;
    for (int i = 1; i <= n; ++i) {
        fact[i] = ((ll)i * fact[i-1]) % mod;
        inv[i] = fastpow(fact[i], mod - 2);
    }
    for (int i = 1; i <= n; ++i) cin >> c[i];
    for (int a,b, i = 0; i < m; ++i) {
        cin >> a >> b;
        V[a].PB(b);
        V[b].PB(a);
    }
    int ans = 1;
    for (int i = 1; i <= n; ++i) {
        if (!vis[i]) {
            int ret = 0;
            o1 = o2 = sz1 = sz2 = 0;
            odd = false;
            dfs(i);
    //        cerr << o1 << " " << o2 << " " << sz1 << " " << sz2 << " " << odd << "\n";
            if (odd) {
                int good = (o1 + o2) & 1;
                for (int s = 0; s <= sz1 + sz2; ++s) {
                    if (s % 2 == good) {
  //                      cerr << sz1 + sz2 << " choose " << s << "\n";
                        ret = (ret + bi(sz1 + sz2, s)) % mod;
                    }
                }
            } else {
                int diff = o2 - o1;
                for (int s = 0; s <= sz1; ++s) {
                    int he = s + diff;
                    if (he < 0 || he > sz2) continue;
                    ret = (ret + (ll)bi(sz1, s) * bi(sz2, he)) % mod;
                }
            }
            ans = ((ll)ans * ret) % mod;
//            cerr << ret << "\n";
        }
    }
    cout << ans;
}