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#include <bits/stdc++.h>
using namespace std;
array<long long,200001> c,rr;
vector<int> d;
array<vector<int>,200001> h;
array<int,200001> g;
array<long long,32> w;
array<long long,32> qq;
long long n,m,i,j,a,b,r,q,x,y,hh,ww,k;
long long p,z;
int main(){
	cin >> n >> m;
	for (i=0;i<n;i++){
		cin >> j;
		c[i]=2*j-1;
	}
	for (i=0;i<m;i++){
		cin >> a >> b;
		h[a-1].push_back(b-1);
		h[b-1].push_back(a-1);
	}
	r=1e+9;
	r+=7;
	hh=r-2;
	for (i=0;i<=30;i++){
		qq[i]=hh%2;
		hh/=2;
	}
	/*for (i=1;i<=100000;i++){
		ww=i;
		hh=1;
		for (j=0;j<=30;j++){
			if (qq[j]){
				hh*=ww;
				hh%=r;
			}
			ww=(ww*ww)%r;			
		}

		rr[i]=hh;
	}*/
	//for (i=1;i<=5;i++)
	//	cout << rr[i] << ' ' << i << ' ' << i*rr[i]%r << '\n';
	//return 0;
	q=1;
	for (i=0;i<n;i++){
		if (g[i])
			continue;
		j=0;
		g[i]=1;
		d={i};
		p=0;
		z=(c[i]+1)/2;
		while (j<d.size()){
			for (auto w:h[d[j]]){
				if (g[w]==g[d[j]]){
					p=1;
					continue;
				}
				if (g[w])
					continue;
				g[w]=-g[d[j]];
				if (c[w]*g[w]>0)
					z++;
				d.push_back(w);
			}
			j++;
		}
		if (p){
				for(j=1;j<d.size();j++) {
					q*=2;
					q%=r;}
		}
		else {
			if(2*z>d.size())
				z=d.size()-z;
			//cout << z << d.size() << '\n';
			for(j=d.size()-z+1;j<=d.size();j++) {
				q*=j;
				q%=r;}
			k=1;
			for(j=1;j<=z;j++){
				k*=j;
				k%=r;
				}
			ww=k;
			hh=1;
			for (j=0;j<=30;j++){
				if (qq[j]){
					hh*=ww;
					hh%=r;
				}
				ww=(ww*ww)%r;			
			}
			q*=hh;
			q%=r;
				}
		}
	cout << q << '\n';
}