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#include<bits/stdc++.h>
using namespace std;
#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<<"{"; for(auto v : x) o<<v<<", "; return o<<"}";}
#define debug(X) cout<<"["#X"]"<<X<<endl;
#else
#define debug(X) {}
#endif
#define int long long
const int MOD = (int)1e9 + (int)7;
vector<int> sil;
int fpow(int a, int b)
{
	if(b == 0) return 1;
	int c = fpow(a, b/2);
	if(b%2 == 0) return (c*c)%MOD;
	return (((c*c)%MOD)*a)%MOD;
}
int newton(int n, int k)
{
	if(k > n) return 0;
	return (sil[n]*fpow((sil[k]*sil[n-k])%MOD, MOD-2))%MOD;
}
int32_t main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int n, m;
	cin>>n>>m;
	sil.push_back(1);
	for(int i=1;i<=n+10;i++) sil.push_back((sil[i-1]*i)%MOD);
	vector<int> tab(n+1);
	for(int i=1;i<=n;i++) cin>>tab[i];
	vector<vector<int> > graph(n+1);
	vector<int> blacks(n+1);
	for(int i=0;i<m;i++)
	{
		int a, b;
		cin>>a>>b;
		graph[a].push_back(b);
		graph[b].push_back(a);
		if(tab[a] == 1) blacks[b]++;
		if(tab[b] == 1) blacks[a]++;
	}
	priority_queue<pair<int, int> > q;
	for(int i=1;i<=n;i++) if(tab[i] == 1 && blacks[i] > 0) q.push({-blacks[i], i});
	while(!q.empty())
	{
		auto a = q.top().second;
		q.pop();
		if(tab[a] == 0) continue;
		debug(a);
		for(auto v : graph[a])
		{
			if(tab[v] == 1)
			{
				tab[a] = 0;
				tab[v] = 0;
				for(auto u : graph[v])
				{
					blacks[u]--;
					if(blacks[u] > 0) q.push({-blacks[u], u});
				}
				break;
			}
		}
	}
	vector<int> parz(n+1, -1);
	function<bool(int, int, int&, int&, int&, int&, int&, int&)> dfs = [&](int a, int d, int& kp, int& knp, int& wp, int& wnp, int& p, int& np)
	{
		parz[a] = d;
		if(tab[a] == 1) 
		{
			if(d%2 == 0) kp++;
			else knp++;
		}
		if(tab[a] == 0)
		{
			if(d%2 == 0) wp++;
			else wnp++;
		}
		if(d%2 == 0) p++; else np++;
		bool out = false;
		for(auto v : graph[a])
		{
			if(parz[v] == -2) continue;
			if(parz[v] != -1)
			{
				if(parz[v]%2 != (d+1)%2) out = true;
				continue;
			}
			out |= dfs(v, d+1, kp, knp, wp, wnp, p, np);
		}
		parz[a] = -2;
		return out;
	};
	debug(tab);
	int result = 1;
	for(int i=1;i<=n;i++)
	{
		if(parz[i] != -1) continue;
		int kp = 0, knp = 0, wp = 0, wnp = 0, p = 0, np = 0;
	       	bool npCycle = false;
		npCycle = dfs(i, 0, kp, knp, wp, wnp, p, np);
		int res = 0;
		if(npCycle == false)
		{
			int delt = abs(kp - knp);
			if(kp > knp) kp = delt, knp = 0;
			else knp = delt, kp = 0;
			wp = p - kp;
			wnp = np - knp;
			for(int j=0;j<min(wp, wnp);j++)
			{
				res += (newton(p, kp)*newton(np, knp))%MOD;
				res %= MOD;
				kp++;
				knp++;
			}
			res += (newton(p, kp)*newton(np, knp))%MOD;
			res %= MOD;
		}
		else
		{
			kp = (kp+knp)%2;
			knp = 0;
			for(int j=0;j<(p+np)/2;j++)
			{
				res += newton(p+np, kp);
				res %= MOD;
				kp+=2;
			}
			res += newton(p+np, kp);
			res %= MOD;
		}
		debug(i);
		debug(npCycle);
		debug(res);
		result *= res;
		result %= MOD;
	}
	cout<<result%MOD;

}