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/*
Things to notice:
1. do not calculate useless values
2. do not use similar names
 
Things to check:
1. submit the correct file
2. time (it is log^2 or log)
3. memory
4. prove your naive thoughts 
5. long long
6. corner case like n=0,1,inf or n=m
7. check if there is a mistake in the ds or other tools you use
8. fileio in some oi-contest

9. module on time 
10. the number of a same divisor in a math problem
11. multi-information and queries for dp and ds problems
*/
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define fi first
#define se second
#define pii pair<long long,long long>
#define mp make_pair
#define pb push_back
const int mod=1e9+7;
const int inf=0x3f3f3f3f;
const int INF=1e18;
int fpow(int x,int b)
{
	if(x==0) return 0;
	if(b==0) return 1;
	int res=1;
	while(b>0)
	{
		if(b&1)	res=1LL*res*x%mod;
		x=1LL*x*x%mod;
		b>>=1;
	}
	return res;
}
int fac[400005],ifac[400005];
int C(int x,int y)
{
	if(y>x) return 0;
	if(x==y||y==0) return 1;
	return 1LL*fac[x]*ifac[x-y]%mod*ifac[y]%mod;
}
void init(int x)
{
	fac[0]=fac[1]=1;
	for(int i=2;i<=x;i++) fac[i]=1LL*fac[i-1]*i%mod;
	ifac[x]=fpow(fac[x],mod-2);  // x should be less than mod!!!
	for(int i=x-1;i>=0;i--) ifac[i]=1LL*ifac[i+1]*(i+1)%mod;
}
int ans=1;
int n,m;
int c[200005],col[200005];
vector <int> g[200005];
int c0,c1,ok=1,d0,d1;
void dfs0(int u,int co)
{
	col[u]=co;
	if(co==0)
	{
		if(c[u]==1) c0++,d0++;
		else d0++;
	}
	else
	{
		if(c[u]==1) c1++,d1++;
		else d1++;
	}
	for(int i=0;i<g[u].size();i++)
	{
		int v=g[u][i];
		if(col[v]==-1) dfs0(v,co^1);
		else if(col[v]!=(co^1)) ok=0;
	}
 } 
void solve()
{
	init(400000);
	cin>>n>>m;
	for(int i=1;i<=n;i++) cin>>c[i];
	memset(col,-1,sizeof(col));
	while(m--)
	{
		int u,v;
		cin>>u>>v;
		g[u].pb(v),g[v].pb(u);
	}
	for(int i=1;i<=n;i++) if(col[i]==-1) 
	{
		c0=c1=d0=d1=0,ok=1,dfs0(i,0);
		if(!ok) ans=1LL*ans*fpow(2,d0+d1-1)%mod;
		else
		{
			int nw=0;
			for(int j=0;j<=d0;j++)
			{
				int k=j+c1-c0;
				if(0<=k&&k<=d1) nw=(nw+C(d0,j)%mod*C(d1,k))%mod;
			}
			ans=1LL*ans*nw%mod;
		}
	}
	cout<<ans<<"\n";
}
signed main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	int _=1;
//	cin>>_;
	while(_--) solve();
	return 0;
}