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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define rep(i, j) for (int i = 0; i < (int)(j); i++)

const int N = 2e5 + 5;

vector<int> g[N];
int col[N];
int inp_col[N];
int vis[N];
ll siln[N];
ll siln_odw[N];

const ll mod = 1e9 + 7;

ll pow_mod(ll x, ll n) {
  if (n == 0)
    return 1;
  if (n == 1)
    return x;
  ll hf = pow_mod(x, n / 2);
  if (n & 1)
    return hf * hf % mod * x % mod;
  return hf * hf % mod;
}

tuple<bool, int, int> dfs(int x, int cur_col) {
  col[x] = cur_col;
  vis[x] = true;
  int nie_ok = inp_col[x] != cur_col;
  int siz = 1;

  bool ok = col;
  for (int el : g[x]) {
    if (!vis[el]) {
      auto [dwu, no, sz] = dfs(el, cur_col ^ 1);
      ok &= dwu;
      nie_ok += no;
      siz += sz;
    } else {
      ok &= col[el] == (cur_col ^ 1);
    }
  }

  return {ok, nie_ok, siz};
}

void TEST([[maybe_unused]] int testcase_i) {
  int n, m;
  cin >> n >> m;
  rep(i, n) {
    cin >> inp_col[i + 1];
  }
  rep(i, m) {
    int a, b;
    cin >> a >> b;
    g[a].push_back(b);
    g[b].push_back(a);
  }

  siln[0] = 1;
  rep(i, N - 1) {
    siln[i + 1] = siln[i] * (i + 1) % mod;
  }
  siln_odw[N - 1] = pow_mod(siln[N - 1], mod - 2);
  for (ll i = N - 2; i >= 0; i--) {
    siln_odw[i] = siln_odw[i + 1] * (i + 1) % mod;
  }

  ll ans = 1;
  rep(i, n) {
    if (!vis[i + 1]) {
      auto [dwu, nie_ok, siz] = dfs(i + 1, 0);
      if (!dwu) {
        ans = ans * pow_mod(2, siz - 1) % mod;
      } else {
        ans = ans * siln[siz] % mod * siln_odw[nie_ok] % mod * siln_odw[siz - nie_ok] % mod;
      }
    }
  }

  cout << ans;
}

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

  cout << setprecision(20) << fixed;

  // srand(time(NULL));

  int t = 1;
  // cin >> t;
  rep(i, t) {
    TEST(i);
  }

  return 0;
}