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

const int NAX = 2e5 + 5;
int lit[NAX];
vector<int> edges[NAX];
int color[NAX];
bool visited[NAX];
bool ok;
int cc_size = 0;
int half;

void dfs(int a) {
	cc_size += 1;
	if (color[a] == lit[a]) {
		half++;
	}
	visited[a] = true;
	for (int b : edges[a]) {
		if (!visited[b]) {
			color[b] = color[a] ^ 1;
			dfs(b);
		}
		else if (color[b] == color[a]) {
			ok = false;
		}
	}
}

const int MOD = 1e9 + 7;

int fac[NAX], inv_fac[NAX];

int choose(int a, int b) {
	return (long long) fac[a] * inv_fac[b] % MOD * inv_fac[a-b] % MOD;
	// return fac[a] / fac[b] / fac[a-b];
}

int my_pow(int a, int b) {
	int r = 1;
	while (b) {
		if (b % 2) {
			r = (long long) r * a % MOD;
		}
		a = (long long) a * a % MOD;
		b /= 2;
	}
	return r;
}
int my_inv(int a) {
	return my_pow(a, MOD - 2);
}

int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(0);
	int n, m;
	cin >> n >> m;
	
	fac[0] = inv_fac[0] = 1;
	for (int i = 1; i <= n; i++) {
		fac[i] = (long long) i * fac[i-1] % MOD;
		inv_fac[i] = my_inv(fac[i]);
	}
	
	for (int i = 1; i <= n; i++) {
		cin >> lit[i];
	}
	for (int i = 0; i < m; i++){ 
		int a, b;
		cin >> a >> b;
		edges[a].push_back(b);
		edges[b].push_back(a);
	}
	int answer = 1;
	for (int a = 1; a <= n; a++) {
		if (!visited[a]) {
			ok = true;
			cc_size = half = 0;
			dfs(a);
			if (ok) { // bipartite
				answer = (long long) answer * choose(cc_size, half) % MOD;
				// cout << "C " << cc_size << " " << half << endl;
			}
			else {
				for (int i = 0; i < cc_size - 1; i++){ 
					answer = 2 * answer % MOD;
				}
			}
		}
	}
	cout << answer << endl;
}