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#include <bits/stdc++.h>
using namespace std;
#ifdef DEBUG
auto&operator<<(auto &o, pair<auto, auto> p) {o << "(" << p.first << ", " << p.second << ")"; return o;}
auto operator<<(auto &o, auto x)->decltype(x.end(), o) {o<<"{"; for(auto e : x) o<<e<<", "; return o<<"}";}
#define debug(X) cerr << "["#X"]: " << X << '\n';
#else 
#define cerr if(0)cout
#define debug(X) ;
#endif
using ll = long long;
#define all(v) (v).begin(), (v).end()
#define ssize(x) int(x.size())
#define fi first
#define se second
#define mp make_pair
#define eb emplace_back

const int mod = 1'000'000'007;

void inc(int &a, int b) {
	a += b;
	if(a >= mod) a -= mod;
}

int mul(int a, int b) {
	return int(((ll)a*b)%mod);
}

int fpow(int a, int b) {
	if(b == 0) return 1;
	if(b%2 == 0) return fpow(mul(a, a), b/2);
	else return mul(a, fpow(a, b-1));
}

int inv(int x) {
	return fpow(x, mod-2);
}

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

	int n, m;
	cin >> n >> m;

	vector<int> c(n);
	for(int i = 0; i < n; ++i) {
		cin >> c[i];
	}

	vector<vector<int>> g(n);
	for(int i = 0; i < m; ++i) {
		int a, b;
		cin >> a >> b;
		a--; b--;
		g[a].eb(b);
		g[b].eb(a);
	}

	vector<int> sil(n+1);
	sil[0] = 1;
	for(int i = 1; i <= n; ++i) sil[i] = mul(i, sil[i-1]);

	auto choose = [&](int a, int b) {
		return mul(sil[a], inv(mul(sil[a-b], sil[b])));
	};

	vector<int> col(n, -1);
	vector<int> sp;
	int a = 0, b = 0; //a = #0, b = #1

	function<bool(int, int)> dfs = [&](int v, int color) {
		col[v] = color;
		sp.eb(v);
		if(color == 0) ++a;
		else ++b;

		bool ok = true;
		for(int u : g[v]) {
			if(col[u] == -1) ok &= dfs(u, 1-color);
			else ok &= (col[u] != col[v]);
		}
		return ok;
	};

	int res = 1;
	for(int i = 0; i < n; ++i) {
		if(col[i] != -1) continue;
		sp.clear();
		int old_a = a, old_b = b;
		bool dwu = dfs(i, 0);

//		debug(sp);
//		debug(dwu);

		if(!dwu) {
			int sz = a+b-(old_a+old_b);
			res = mul(res, fpow(2, sz-1));
		}
		else {
			int da = a - old_a, db = b-old_b;
//			debug(da);
//			debug(db);
			int x = 0, y = 0;
			for(int v : sp) {
				if(c[v] == 0) continue;
				if(col[v] == 0) ++x;
				else ++y;
			}
//			debug(x);
//			debug(y);
			assert(x <= da && y <= db);

			int podz = 0;
			if(x >= y) {
//				debug(x-y);
				for(int k = x-y; k <= da && k-(x-y) <= db; ++k) {
//					debug(k);
					assert(k >= 0 && k <= da);
					assert(k-(x-y) >= 0);
					assert(k-(x-y) <= db);
					inc(podz, mul(choose(da, k), choose(db, k-(x-y))));
				}
			}
			else {
				debug(y-x);
				for(int k = y-x; k <= db && k-(y-x) <= da; ++k) {
//					debug(k);
					assert(k >= 0 && k <= db);
					assert(k-(y-x) >= 0 && k-(y-x) <= da);
					inc(podz, mul(choose(da, k-(y-x)), choose(db, k)));
				}
			}
//			debug(podz);
			res = mul(res, podz);
			//res *= ile jest podzialow tak ze liczba 1 w da - liczba 1 w db == x-y
		}
//		debug(res);
//		cerr << endl;
	}

	cout << res << '\n';

	return 0;
}