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#include <bits/stdc++.h>
using namespace std;
//{
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define VAR(v, i) __typeof(i) v=(i)
#define all(v) (v).begin(),(v).end()
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)


#define PII pair<int,int>
#define st first
#define nd second
#define pb push_back
#define lint long long int
#define VI vector<int>

#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
};
//{
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

#define make( x) int (x); scanf("%d",&(x));
#define make2( x, y) int (x), (y); scanf("%d%d",&(x),&(y));
#define make3(x, y, z) int (x), (y), (z); scanf("%d%d%d",&(x),&(y),&(z));
#define make4(x, y, z, t) int (x), (y), (z), (t); scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define makev(v,n) VI (v); FOR(i,0,(n)) { make(a); (v).pb(a);} 
#define IOS ios_base::sync_with_stdio(0)
#define HEAP priority_queue

#define read( x) scanf("%d",&(x));
#define read2( x, y) scanf("%d%d",&(x),&(y));
#define read3(x, y, z) scanf("%d%d%d",&(x),&(y),&(z));
#define read4(x, y, z, t) scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define readv(v,n) FOR(i,0,(n)) { make(a); (v).pb(a);}
#define jeb() fflush(stdout);

int mod = 1e9+7;

int n, m;

int inv[200005];
int fac[200005]; 
int ifac[200005];
int p2[200005];
int col[200005];

VI g[200005];
int visited[200005];
int kolor[200005];

VI v0, v1;
bool ok = true;

void dfs(int v) {
	if (kolor[v] == 0) v0.pb(v);
	else if(kolor[v] == 1) v1.pb(v);
	FORE(i, g[v]) {
		int w = *i;
		if (visited[w]) {
			if (kolor[w] == kolor[v]) ok = false;
		} else {
			visited[w] = 1;
			kolor[w] = 1 - kolor[v];
			dfs(w);
		}
	}
}

int newton(int a, int b) {
	if (b < 0 || b > a) return 0;
	return ((fac[a] * 1LL * ifac[b])%mod * ifac[a-b])%mod;
}

int main() {
	read2(n, m);
	fac[0] = 1;
	FOR(i,1,n+1) fac[i] = (i * 1LL * fac[i-1]) % mod;
	inv[1] = 1; ifac[1] = 1; ifac[0] = 1;
	FOR(i,2,n+1) {
		int q = mod/i;
		int r = mod%i;
		inv[i] = ((mod-q) * 1LL * inv[r])%mod;
		ifac[i] = (ifac[i-1] * 1LL * inv[i]) % mod;
	}
	p2[0] = 1;
	FOR(i,1,n+1) p2[i] = (p2[i-1]*2)%mod;

	FOR(i,0,n) {
		make(a); col[i] = a;
	}
	FOR(i,0,m) {
		make2(a, b);
		a--; b--;
		g[a].pb(b);
		g[b].pb(a);
	}
	
	FOR(i,0,n) visited[i] = 0;
	FOR(i,0,n) kolor[i] = -1;
	
	VI skladowe;
	FOR(i,0,n) {
		if (visited[i] == 0) {
			v0.clear(); v1.clear(); ok = true;
			visited[i] = 1; kolor[i] = 0;
			dfs(i);
			if (!ok) {
				skladowe.pb(p2[v0.size()+v1.size()-1]);
			} else {
				int cnt = 0;
				FOR(j,0,v0.size()) cnt += col[v0[j]];
				FOR(j,0,v1.size()) cnt -= col[v1[j]];
				int n0 = v0.size();
				int n1 = v1.size();
				int local = 0;
				FOR(w,0,n1+1) {
					int u = w + cnt; 
					local += (newton(n1, w) * 1LL * newton(n0,u)) % mod;
					local %= mod;
				}
				skladowe.pb(local);
			}
		}
	}
	int ans = 1;
	FOR(i,0,skladowe.size()) {
		ans = (ans * 1LL * skladowe[i]) % mod;
	}
	printf("%d\n", ans);
}