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

const LL MOD = 1e9 + 7;

int n, m;
vector<bool> d;
vector<int> v[200009];

int odw[200009];

LL xGCD(LL a, LL b, LL &x, LL &y) {
	if (b == 0) {
		x = 1;
		y = 0;
		return a;
	}

	LL x1, y1, gcd = xGCD(b, a % b, x1, y1);
	x = y1;
	y = x1 - (a / b) * y1;
	return gcd;
}

LL modfact(LL n) {
	LL result = 1;
	while (n > 1) {
		result = result * n % MOD;
		n -= 1;
	}
	return result;
}

LL modmult(LL a, LL b) {
	return a * b % MOD;
}

LL inverse(LL a) {
	LL x, y;
	xGCD(a, MOD, x, y);
	return x;
}

LL bc(LL n, LL k) {
	return modmult(modmult(modfact(n), inverse(modfact(k))), inverse(modfact(n - k)));
}

int zlicz = 0;
int pa[2], ni[2];

pair<int, int> dfs(int st, int x) {
	odw[st] = x;
	zlicz++;
	if(d[st]){
		pa[x%2]++;
	}else{
		ni[x%2]++;
	}
	pair<int, int> res = {zlicz, 0};
	for (auto q : v[st]) {
		if (odw[q] == 0) {
			auto [a, b] = dfs(q, x + 1);
			res.first = max(res.first, a);
			res.second = max(res.second, b);
		} else {
			if ((x + odw[q]) % 2 == 0) {
				res.second = 1;
			}
		}
	}
	return res;
}


LL solve() {
	LL res = 1;
	for (int i = 0; i < n; i++) {
		if (odw[i] == 0) {
			zlicz = 0;
			for(int j=0; j<2; j++){
				pa[j] = 0;
				ni[j] = 0 ;
			}
			auto [a, b] = dfs(i, 1);
			if (b == 1) {
				LL ans = 1;
				for (int i = 1; i < a; i++) {
					ans = (ans * 2) % MOD;
				}
				res = (res * ans) % MOD;
			} else {
				int ile = min(pa[0] + ni[1], pa[1] + ni[0]);
				res = (res * (bc(a, ile) + MOD)) % MOD;
			}
		}
	}
	return res;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);

	cin >> n >> m;
	for (int i = 0; i < n; i++) {
		bool a;
		cin >> a;
		d.push_back(a);
	}
	for (int i = 0; i < m; i++) {
		int a, b;
		cin >> a >> b;
		a--;
		b--;
		v[a].push_back(b);
		v[b].push_back(a);
	}
	cout << solve() << "\n";

	return 0;
}