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// {{{ file: zar.cc | time: 09:14 16.03.2024
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>

#define each(...)    for (auto& __VA_ARGS__)
#define rep(i, b, e) for (int i = (b); i <= (e); i++)
#define rev(i, b, e) for (int i = (e); i >= (b); i--)
#define mp make_pair
#define mt make_tuple
#define x first
#define y second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define endl '\n'
#define tC template<class

using namespace std;

tC T> using V = vector<T>;
tC T1, class T2> using P = pair<T1,T2>;
tC T, class C=greater<T>> using PQ = priority_queue<T,V<T>,C>;
tC T> int sz(const T& a) { return (int)a.size(); }
tC T> bool amin(T& a, T b) { return b < a ? a = b, 1 : 0; }
tC T> bool amax(T& a, T b) { return b > a ? a = b, 1 : 0; }

using ll = long long;
using pii = P<int,int>;
using pll = P<ll,ll>;
using vi = V<int>;
using vl = V<ll>;
using vs = V<string>;
using vpi = V<pii>;
using vpl = V<pll>;

const int oo = 1e9 + 1;
const ll OO = ll(1e18) + 1;

auto now() { return chrono::high_resolution_clock::now().time_since_epoch().count(); }
mt19937 rnd(4488);
tC T> T rand(T lo, T hi) { return uniform_int_distribution<T>{lo,hi}(rnd); }

struct Debug {
#ifdef SPONGE
  tC T>Debug operator<<(const T& x) {
    cerr<<"\033[1;33m"<<x<<"\033[0m";
#else
  tC T>Debug operator<<(const T&) {
#endif
    return *this;
  }
} dbg;
#define $(x) #x<<'='<<(x)<<' '

void boost()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.precision(15);
  cout.setf(ios::fixed,ios::floatfield);
  cerr.precision(15);
  cerr.setf(ios::fixed,ios::floatfield);
}

namespace { void solve(); }
// }}}

int main()
{
  boost();
  //rnd.seed(now());
  int t=1;
  //cin>>t;
  rep(i,1,t){
    //cout<<"Case #"<<i<<": ";
    solve();
  }
}

namespace {

const int N=2e5+5;
const int mod=1e9+7;

int n,m,stan[N],kolor[N];
vi graf[N];
bool is_odd,is_move;
int ile[3][2];
ll odp=1;

ll fact[N],invfact[N];

ll pot(ll a,ll b)
{
  ll c=1;
  while(b>0){
    if(b%2==1) c=a*c%mod;
    a=a*a%mod;
    b/=2;
  }
  return c;
}

ll odw(ll a)
{
  return pot(a,mod-2);
}

ll choose(int k,int l){
  if(k<0 || l>k) return 0;
  return fact[k]*invfact[l]%mod*invfact[k-l]%mod;
}

void dfs(int v,int c)
{
  if(kolor[v]){
    if(kolor[v]!=c) is_odd=1;
  }
  else{
    kolor[v]=c;
    ile[c][stan[v]]++;
    each(u:graf[v]){
      if(stan[u]==stan[v]) is_move=1;
      dfs(u,3-c);
    }
  }
}

void solve()
{
  cin>>n>>m;
  rep(i,1,n) cin>>stan[i];

  fact[0]=1;
  invfact[0]=1;
  rep(i,1,n){
    fact[i]=fact[i-1]*i%mod;
    invfact[i]=odw(fact[i]);
  }

  rep(i,1,m){
    int u,v;
    cin>>u>>v;
    graf[u].pb(v);
    graf[v].pb(u);
  }

  rep(i,1,n) if(!kolor[i]){
    is_odd=0;
    is_move=0;
    rep(x,1,2) rep(y,0,1) ile[x][y]=0;
    dfs(i,1);

    if(is_odd){
      int k=0;
      rep(x,1,2) rep(y,0,1) k+=ile[x][y];
      int x=k,xd=0;
      if(x%2 != (ile[1][1]+ile[2][1])%2) x--;
      while(x>=0) {xd=(xd+choose(k,x))%mod; x-=2;}
      odp=odp*ll(xd)%mod;
    }
    else if(is_move){
      int k1=ile[1][0]+ile[1][1];
      int k2=ile[2][0]+ile[2][1];
      int x=max(ile[1][0]-k1,ile[2][0]-k2);
      int xd=0;
      while(ile[1][0]>=x && ile[2][0]>=x){
        xd+=choose(k1,ile[1][0]-x)*choose(k2,ile[2][0]-x)%mod;
        xd%=mod;
        x++;
      }
      odp=odp*ll(xd)%mod;
    }
  }

  cout<<odp<<endl;
}

}