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#include<bits/stdc++.h>
using namespace std;
typedef long double ld;
typedef long long ll;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const ll MOD=1e9+7;
const int LIM=2e5+7;
vector<int>V[LIM];
ll T[LIM], kol[LIM], sil[LIM], osil[LIM], ile[3], sum[3];
bool dwu;
ll pot(ll a, ll b) {
  ll ans=1;
  while(b) {
    if(b&1) ans=(ans*a)%MOD;
    a=(a*a)%MOD;
    b/=2;
  }
  return ans;
}
ll C(ll n, ll k) {
  if(k>n) return 0;
  return (((sil[n]*osil[k])%MOD)*osil[n-k])%MOD;
}
void DFS(int x) {
  ++ile[kol[x]];
  if(T[x]) ++sum[kol[x]];
  for(auto i : V[x]) {
    if(!kol[i]) {
      kol[i]=kol[x]^3;
      DFS(i);
    } else if(kol[i]==kol[x]) dwu=false;
  }
}
int main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  sil[0]=osil[0]=1;
  for(ll i=1; i<LIM; ++i) {
    sil[i]=(sil[i-1]*i)%MOD;
    osil[i]=pot(sil[i], MOD-2);
  }
  int n, m;
  cin >> n >> m;
  rep(i, n) cin >> T[i];
  rep(i, m) {
    int a, b;
    cin >> a >> b; --a; --b;
    V[a].pb(b);
    V[b].pb(a);
  }
  ll ans=1;
  rep(i, n) if(!kol[i]) {
    ile[1]=ile[2]=sum[1]=sum[2]=0;
    dwu=true;
    kol[i]=1;
    DFS(i);
    if(!dwu) {
      ans=(ans*pot(2, ile[1]+ile[2]-1))%MOD;
      continue;
    }
    if(dwu) ans=(ans*C(ile[1]+ile[2], sum[1]-sum[2]+ile[2]))%MOD;
  }
  cout << ans << '\n';
}