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/*
 * Opis: Główny nagłówek
 */
#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r)for(int i=(l);i<=(r);++i)
#define REP(i,n)FOR(i,0,(n)-1)
#define ssize(x)int(x.size())
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

const LL mod = 1e9 + 7;

struct Binom {
	int s;
	vector<LL> fact, inv, inv_fact, pow2;

	Binom(int _s) {
		s = _s;
		fact.resize(s + 1, 1);
		inv.resize(s + 1, 1);
		inv_fact.resize(s + 1, 1);
		pow2.resize(s + 1, 1);
		pow2[1] = 2;
		FOR(i, 2, s) {
			pow2[i] = pow2[i - 1] * 2 % mod;
			fact[i] = fact[i - 1] * i % mod;
			inv[i] = (mod - inv[mod % i] * (mod / i) % mod) % mod;
			inv_fact[i] = inv_fact[i - 1] * inv[i] % mod;
		}
	}

	LL get(int n, int k) {
		if (n < k || k < 0) {
			return 0;
		}
		return fact[n] * inv_fact[k] % mod * inv_fact[n - k] % mod;
	}

	LL get_pow(int ind) {
		return pow2[ind];
	}
};

struct Graph {
	int n, m;
	vector<int> bits;
	vector<vector<int> > kraw;
	vector<bool> vis;
	vector<int> col;
	array<int, 2> l;
	array<int, 2> k;
	bool bipart;

	Graph(int _n, int _m, vector<vector<int> > &_kraw, vector<int> &_bits) {
		n = _n;
		m = _m;
		swap(kraw, _kraw);
		swap(bits, _bits);
		vis.resize(n);
		col.resize(n);
	}

	void check_col(int x, int curr) {
		col[x] = curr;
		vis[x] = true;
		l[curr - 1]++;
		k[curr - 1] += bits[x];
		for (int v : kraw[x]) {
			if (vis[v] && col[x] == col[v]) {
				bipart = false;
			}
			if (!vis[v]) {
				check_col(v, 3 - curr);
			}
		}
	}

	LL solve() {
		Binom binom(n);
		LL res = 1;
		REP(i, n) {
			if (kraw[i].empty()) {
				continue;
			}
			if (!vis[i]) {
				l = {0, 0};
				k = {0, 0};
				bipart = true;
				check_col(i, 1);
				if (!bipart) {
					res = res * binom.get_pow(l[0] + l[1] - 1) % mod;
				}
				else {
					int ile = min(k[0], k[1]);
					k[0] -= ile;
					k[1] -= ile;
					// debug(k, l);
					LL new_res = 0;
					REP(j, min(l[0], l[1])+1) {
						// debug(l[0], k[0]+j, l[1], k[1]+j);
						new_res = (new_res + binom.get(l[0], k[0]+j) * binom.get(l[1], k[1]+j)) % mod;
					}
					res = res * new_res % mod;
				}
			}
		}
		return res;
	}

};

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n, m;
	cin >> n >> m;
	vector<int> bits(n);
	vector<vector<int> > kraw(n);
	REP(i, n) {
		cin >> bits[i];
	}
	REP(i, m) {
		int a, b;
		cin >> a >> b;
		a--;
		b--;
		kraw[a].push_back(b);
		kraw[b].push_back(a);
	}
	Graph g(n, m, kraw, bits);
	cout << g.solve() << "\n";
}