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#include<cstdio>
#include<algorithm>
#include<utility>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<cmath>
#include<iostream>

// macros

#define FORE(c, a, b) for(int c=a; c<= int(b); ++c)
#define FORD(c, a, b) for(int c=a; c>= int(b); --c)
#define FORIT(it, cont, cont_t) for(cont_t::iterator it = cont.begin(); it != cont.end(); ++it)
#define REP(i, n) for(int i = 0; i < (n); ++i)
#define ALL(a) a.begin(), a.end() 
#define PR(n) printf("%d ", (int) (n)) 
#define PRL(n) printf("%lld ", (ll) (n)) 
#define SC(n) scanf("%d", &n);
#define SC2(n, m) scanf("%d%d", &n, &m);

#define xx first
#define yy second
#define pb push_back
#define mp make_pair
#define itr iterator

#define dbg if(0)
#define prd dbg printf

using namespace std;

typedef long long ll;
typedef long double ld;
typedef unsigned int uint;

typedef vector<int> vi;
typedef set<int> si;
typedef map<int, int> mi;
typedef pair<int, int> pi;
typedef vector<pi> vii;
typedef vector<vi> vvi;

const int NMAX = 1<<20, MOD = 1000000007;

int n, m, k;
int cc_size, cc_ones, cc_red, cc_blue, zar_red, zar_blue, non_bip;
int zar[NMAX], vis[NMAX];
vi edges[NMAX];
ll ans = 1;
ll fact[NMAX];

ll power(ll x, int m) {
  //prd("power %lld %d\n", x, m);
  if (m==0) return 1;
  if (m==1) return x;
  if (m % 2) return (x * power(x, m-1)) % MOD;
  ll y = power(x, m/2);
  return (y * y) % MOD; 
}

ll choose(int nn, int kk) {
  ll temp = (fact[nn] * power(fact[kk], MOD - 2)) % MOD;
  return (temp * power(fact[nn - kk], MOD - 2)) % MOD;
}

ll binom(int nn, int par) {
  prd("binom %d %d\n", nn, par);
  ll bin_ans = 0;
  FORE(i, 0, nn) if((i % 2) == par) {
    bin_ans = (bin_ans + choose(nn, i)) % MOD;
    prd("add %d = %lld\n", i, bin_ans);
  }
  return bin_ans;
}

void dfs(int v, int col) {
  vis[v] = col;

  if (col == 1) {
    cc_red++;
    zar_red += zar[v];
  }
  else {
    cc_blue++;
    zar_blue += zar[v];
  }

  int col2 = 3 - col;

  cc_size++;
  cc_ones += zar[v];

  FORIT(it, edges[v], vi) {
    int u = *it;
    if (vis[u] == col2)
      continue;
    if (vis[u] == col) {
      non_bip = 1;
      continue;
    }
    dfs(u, col2);
  }
}

int main() {
  SC2(n, m);
  REP(i, n)
    SC(zar[i+1]);
  REP(i, m) {
    int u, v;
    SC2(u, v);
    edges[u].pb(v);
    edges[v].pb(u);
  }

  fact[0] = 1;
  FORE(i, 1, n)
    fact[i] = (fact[i-1] * i) % MOD;

  FORE(v, 1, n) if(!vis[v]) {
    cc_size = cc_ones = cc_red = cc_blue = zar_red = zar_blue = non_bip = 0;

    ll cc_ans = 0;
    dfs(v, 1);

    if (non_bip)
      cc_ans = binom(cc_size, cc_ones % 2);
    else {
      //int red_min_blue = zar_red - zar_blue;
      FORE(iblue, 0, cc_blue) {
        int ired = iblue + zar_red - zar_blue;
        if (ired < 0 || ired > cc_red)
          continue;
        cc_ans += choose(cc_red, ired) * choose(cc_blue, iblue);
        cc_ans = cc_ans % MOD; 
      }
    }
    prd("cc_size %d cc_ones %d cc_red %d cc_blue %d zar_red %d zar_blie %d non_bip %d cc_ans %lld\n", cc_size, cc_ones, cc_red, cc_blue, zar_red, zar_blue, non_bip, cc_ans);
    ans = (ans * cc_ans) % MOD;
  }

  printf("%lld", ans);
  return 0;
}