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#include <bits/stdc++.h>

#define ll long long
#define fors(u, n, s) for(ll u = (s); u < (n); u++)
#define foru(u, n) fors(u, n, 0)
#define vec vector
#define pb push_back
#define f first
#define s second
#define ir(a, b, x) (((a) <= (x)) && ((x) <= (b)))
#define pint pair<int, int>
#define us unsigned

using namespace std;

const int N = 3e5;
const int M = 1e9+7;

int inv(int a) {
  return a <= 1 ? a : M - (long long)(M/a) * inv(M % a) % M;
}

ll power_of_two[N];
ll factorial[N];

vec<int> adj[N];

int color[N];
bool visited[N];
bool my_set[N];

bool dwudzielny = true;

int sz = 0;
int cnt = 0;

void dfs(int x, int c){
	if(color[x]==0){
		color[x] = c;
	}else if(color[x] != c) dwudzielny=false;
	if(visited[x]) return;
	visited[x]=true;
	
	sz ++;
	cnt += my_set[x]^(color[x]-1);
	for(auto i : adj[x]) dfs(i, 3-c);
}

ll solve_compontent(int x){
	dwudzielny = true;
	sz = 0;
	cnt = 0;
	dfs(x, 1);
	if(dwudzielny){
		ll ans = factorial[sz];
		ans *= inv(factorial[cnt]); ans %= M;
		ans *= inv(factorial[sz-cnt]); ans %=M;
		return ans;
	}else{
		return power_of_two[sz-1];
	}
}

int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

	power_of_two[0]=1;
	factorial[0]=1;

	fors(i, N, 1){
		power_of_two[i] = (2*power_of_two[i-1])%M;
		factorial[i] = (i*factorial[i-1])%M;
	}

	int n; cin >> n;
	int k; cin >> k;

	foru(i, n) {
		int x; cin >> x;
		my_set[i]=x;
	}
	
	foru(_i, k){
		int a, b; cin >> a >> b; a--; b--;
		adj[a].pb(b); adj[b].pb(a);
	}

	ll out = 1;
	foru(i, n){
		if(visited[i]) continue;
		out *= solve_compontent(i);
		out = out%M;
	}

	cout << out;

}