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#ifdef LOCAL
class SS {
   int x[0];
};
extern "C" SS __sanitizer_print_stack_trace();
#define __last_state                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   \
   }                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   \
   ;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   \
   SS x {                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              \
      __sanitizer_print_stack_trace()
#endif
#include <bits/stdc++.h>
#include <chrono>
#include <ext/pb_ds/assoc_container.hpp>
#include <math.h>
using namespace __gnu_pbds;
using namespace std;
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define vi vector<int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10), cin.tie(0), cout.tie(0);
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define all(c) (c).begin(), (c).end()
#define sz(X) (int)((X).size())
typedef long double ld;
typedef unsigned long long ull;
typedef long long ll;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> indexed_set; // find_by_order(x) <-returns x-th element   order_of_key(x) <- returns order of element x
// mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());uniform_int_distribution<int> distr(0, 1e9);auto my_rand = bind(distr, gen); // my_rand() zwraca teraz liczbe z przedzialu [a, b]
#ifdef LOCAL
ostream &operator<<(ostream &out, string str) {
   for (char c : str)
      out << c;
   return out;
}
template <class L, class R> ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.st << ", " << p.nd << ")"; }
template <class L, class R, class S> ostream &operator<<(ostream &out, tuple<L, R, S> p) {
   auto &[a, b, c] = p;
   return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
   out << '{';
   for (auto it = a.begin(); it != a.end(); it = next(it))
      out << (it != a.begin() ? ", " : "") << *it;
   return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts> void dump(T a, Ts... x) {
   cerr << a << ", ";
   dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...) ;
#endif

#define int long long
const ll mod = 1e9 + 7;

ull mod_mul(ull a, ull b) { return a * b % mod; }
ull mod_pow(ull b, ull e) {
   ull ans = 1;
   for (; e; b = b * b % mod, e /= 2)
      if (e & 1)
         ans = ans * b % mod;
   return ans;
}

ull inv(ull a) { return mod_pow(a, mod - 2); }

const int MAXF = 2e5 + 99;
const int MAXN = MAXF;
ll F[MAXF], I[MAXF];

void pre() {
   F[0] = I[0] = 1;
   for (int i = 1; i < MAXF; i++) {
      F[i] = mod_mul(i, F[i - 1]);
      I[i] = inv(F[i]);
   }
}
ll binom(int a, int b) {
   assert(a >= b);
   return mod_mul(mod_mul(F[a], I[b]), I[a - b]);
}
int pt2(int x) {
   int res = 0;
   rep(i, x + 1) res += binom(x, i);
   return res % mod;
}

#define DWA 2
int clr[MAXN];
vector<int> G[MAXN];
vector<int> T;

void dfs(int x, bool &good) {
   T.push_back(x);
   for (int y : G[x]) {
      if (!clr[y]) {
         clr[y] = clr[x] ^ 1;
         dfs(y, good);
      }
      good = good and (clr[y] == (clr[x] ^ 1));
   }
}

int32_t main() {
   _upgrade;
   pre();

   int n, m;
   cin >> n >> m;
   vector<int> S(n);
   for (auto &s : S)
      cin >> s;

   rep(i, m) {
      int a, b;
      cin >> a >> b;
      G[--a].push_back(--b);
      G[b].push_back(a);
   }
   int res = 1;

   rep(i, n) if (!clr[i]) {
      clr[i] = DWA;
      bool dwudzielny = true;
      T.clear();

      dfs(i, dwudzielny);
      debug(T, dwudzielny);
      if (!dwudzielny)
         res = res * pt2(sz(T) - 1) % mod;
      else {
         int ile[2] = {0, 0};
         int ilec[2] = {0, 0};
         for (int t : T) {
            int idx = (clr[t] == DWA);
            ile[idx]++;
            ilec[idx] += S[t];
         }
         int _tmp = 0;
         for (int t = -min(ilec[0], ilec[1]); t <= min(ile[0] - ilec[0], ile[1] - ilec[1]); t++) {
            auto A = binom(ile[0], ilec[0] + t);
            auto B = binom(ile[1], ilec[1] + t);
            _tmp += A * B % mod;
         }
         res = res * (_tmp % mod) % mod;
      }
   }
   cout << res << endl;
}