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#include<set>
#include<map>
#include<queue>
#include<vector>
#include<algorithm>
#include<bits/stdc++.h>
#define pr pair
#define f first
#define s second
#define ll long long
#define mp make_pair
#define pll pr<ll,ll>
#define pii pr<int,int>
#define piii pr<int,pii>
using namespace std;
bool vd[200005];
vector<int> e[200005];
int s[200005];
int cl[200005];
const ll m=1e9+7,mo=m;
ll pw(ll a,ll b=m-2)
{
	ll r=1;
	while(b>0)
	{
		if(b&1) r=r*a%m;
		b>>=1;
		a=a*a%m;
	}
	return r;
}
ll C(ll a,ll b)
{
	ll r=1;
	for(int i=1;i<=b;i++)
	{
		r=r*(a-i+1)%m;
		r=r*pw(i)%m;
	}
	return r;
}
ll cal(int x)
{
	queue<int> q;
	bool bd=0;
	int cnt=0,tot=0;
	q.push(x);
	vd[x]=1;
	while(q.size())
	{
		int f=q.front();
		q.pop();
		tot++;
//		cout<<"Fn "<<f<<endl;
		if(cl[f]^s[f]) cnt++;
		for(int t:e[f])
		{
			if(vd[t])
			{
				if(cl[t]==cl[f]) bd=1;
			}
			else
			{
				cl[t]=cl[f]^1;
				vd[t]=1;
				q.push(t);
			}
		}
	}
//	cout<<"F "<<bd<<' '<<tot<<' '<<cnt<<endl;
	if(bd) return pw(2,tot-1);
	return C(tot,cnt);
}
int main()
{
	ios_base::sync_with_stdio(0);
	int n,m;
	cin>>n>>m;
	int u,v;
	for(int i=0;i<n;i++) cin>>s[i];
	for(int i=0;i<m;i++)
	{
		cin>>u>>v;
		u--;
		v--;
		e[u].push_back(v);
		e[v].push_back(u);
	}
	ll ans=1;
	for(int i=0;i<n;i++)
	{
		if(vd[i]) continue;
		ans=ans*cal(i)%mo;
	}
	cout<<ans<<endl;
	return 0;
}