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

vector <bool> v;
vector <bool> vis;
vector <vector <int> > g;
vector <int> gr;
bool np = 0;
const ll mod = 1e9+7;
int sz = 0;
array <int, 2> ilewg;
array <int, 2> ile1wg;


void dfs(int a) {
	vis[a] = 1;
	sz++;
	for (auto b : g[a]) {
		if (!vis[b]) {
			gr[b] = !gr[a];
			ilewg[gr[b]]++;
			if (v[b]) 
				ile1wg[gr[b]]++;
			dfs(b);
		}
		else if (gr[b] == gr[a]) {
			np = 1;
		}
	}
}

ll powmod(ll a, ll b) {
	ll res = 1;
	while (b > 0) {
		if (b % 2)
			res *= a;
		a *= a;
		a %= mod;
		res %= mod;
		b /= 2;
	}
	return res;
}

vector <ll> sil;

ll dwumian(ll n, ll k) {
	ll res = sil[n];
	res *= powmod(sil[k], mod-2);
	res %= mod;
	res *= powmod(sil[n-k], mod-2);
	res %= mod;
	return res;
}


int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n, m;
	cin >> n >> m;
	g.resize(n);
	gr.resize(n);
	v.resize(n);
	vis.resize(n);
	for (int i = 0; i < n; i++) {
		bool x;
		cin >> x;
		v[i] = x;
	}
	for (int i = 0; i < m; i++) {
		int a, b;
		cin >> a >> b;
		a--; b--;
		g[a].push_back(b);
		g[b].push_back(a);
	}


	sil.resize(200000);
	sil[0] = 1;
	sil[1] = 1;
	for (int i = 2; i < 200000; i++) {
		sil[i] = sil[i-1] * i;
		sil[i] %= mod;
	}


	ll res = 1;
	for (int i = 0; i < n; i++) {
		if (!vis[i]) {
			np = 0;
			sz = 0;
			ilewg = {1, 0};
			ile1wg = {0, 0};
			if (v[i]) ile1wg[0]++;
			dfs(i);
			if (np) {
				ll temp = powmod(2, sz-1);
				res *= temp;
				res %= mod;
			}
			else {
				if (ile1wg[1] > ile1wg[0]) {
					swap(ile1wg[1], ile1wg[0]);
					swap(ilewg[1], ilewg[0]);
				}
				int roz = ile1wg[0] - ile1wg[1];
				ll temp = 0;
				for (int j = 0; j <= min(ilewg[0] - roz, ilewg[1]); j++) {
					temp += dwumian(ilewg[0], j+roz) * dwumian(ilewg[1], j);
					temp %= mod;
				}
				res *= temp;
				res %= mod;
			}
		}
	}
	cout << res << "\n";
}