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#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 2137
#endif

const uint32_t MOD = 1000000007;
 
struct mint {
  uint32_t val;
 
  mint(ll v = 0) {
    v %= MOD;
    if (v < 0) {
      v += MOD;
    }
    val = v;
  }
 
  mint& operator+=(const mint& other) {
    val += other.val;
    if (val >= MOD) {
      val -= MOD;
    }
    return *this;
  }
 
  mint& operator-=(const mint& other) {
    val += MOD - other.val;
    if (val >= MOD) {
      val -= MOD;
    }
    return *this;
  }
 
  mint& operator*=(const mint& other) {
    val = (uint64_t)val * other.val % MOD;
    return *this;
  }
 
  mint& operator/=(const mint& other) {
    return *this *= other.inv();
  }
 
  friend mint operator+(mint a, const mint& b) { return a += b; }
  friend mint operator-(mint a, const mint& b) { return a -= b; }
  friend mint operator*(mint a, const mint& b) { return a *= b; }
  friend mint operator/(mint a, const mint& b) { return a /= b; }
 
  mint pow(ll exp) const {
    mint a = *this;
    mint res = 1;
    while (exp > 0) {
      if (exp & 1) {
        res *= a;
      }
      a *= a;
      exp /= 2;
    }
    return res;
  }
 
  mint inv() const {
    assert(val != 0);
    return pow(MOD - 2);
  }
 
  friend ostream& operator<<(ostream& os, const mint& m) {
    return os << m.val;
  }
};

vector<mint> _f = {1}, _fi = {1};

void _init(int n) {
  int k = ssize(_f);
  if (n < k) {
    return;
  }
  n *= 2;
  _f.resize(n + 1);
  _fi.resize(n + 1);
  for (int i = k; i <= n; i++) {
    _f[i] = _f[i - 1] * i;
  }
  _fi[n] = _f[n].inv();
  for (int i = n; i > k; i--) {
    _fi[i - 1] = _fi[i] * i;
  }
}

mint fact(int n) {
  _init(n);
  return _f[n];
}

mint inv_fact(int n) {
  _init(n);
  return _fi[n];
}

mint choose(int n, int k) {
  if (n < k || k < 0) {
    return 0;
  }
  _init(n);
  return _f[n] * _fi[k] * _fi[n - k];
}

const int N = 200200;
int n, m;
int a[N];
vector<int> adj[N];
int c[N];
int sz = 0;
bool czy = true;
int cnt[2] = {0, 0};
int s[2] = {0, 0};

void dfs(int u) {
  cnt[c[u]] += a[u];
  s[c[u]]++;
  sz++;
  for (int v : adj[u]) {
    if (c[v] == -1) {
      c[v] = c[u] ^ 1;
      dfs(v);
    } else if (c[v] != (c[u] ^ 1)) {
      czy = false;
    }
  }
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    u--; v--;
    adj[u].push_back(v);
    adj[v].push_back(u);
  }
  mint ans = 1;
  for (int i = 0; i < n; i++) {
    c[i] = -1;
  }
  for (int i = 0; i < n; i++) {
    if (c[i] != -1) {
      continue;
    }
    sz = 0;
    c[i] = 0;
    czy = true;
    cnt[0] = cnt[1] = s[0] = s[1] = 0;
    dfs(i);
    if (czy) {
      mint sum = 0;
      for (int j = 0; j <= s[0]; j++) {
        sum += choose(s[0], j) * choose(s[1], j - cnt[0] + cnt[1]);
      }
      ans *= sum;
    } else {
      ans *= mint(2).pow(sz - 1);
    }
  }
  cout << ans << '\n';
}