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#if defined(EMBE_DEBUG) && !defined(NDEBUG)
#include "embe-debug.hpp"
#else
#define LOG_INDENT(...) do {} while (false)
#define LOG(...) do {} while (false)
#define DUMP(...) do {} while (false)
#endif

#include <iostream>
#include <vector>
using namespace std;

namespace {

constexpr int modulo = 1'000'000'007;

int mul(int a, int b)
{
  return static_cast<long long>(a) * b % modulo;
}

int power(int a, int b)
{
  if (b == 0) return 1;
  auto tmp = power(a, b / 2);
  auto tmp2 = mul(tmp, tmp);
  if (b % 2 == 0) {
    return tmp2;
  } else {
    return mul(tmp2, a);
  }
}

int div(int a, int b)
{
  return mul(a, power(b, modulo - 2));
}

int fact(int n)
{
  int res = 1;
  for (int i = 2; i <= n; ++i) {
    res = mul(res, i);
  }
  return res;
}


int choose(int n, int k)
{
  return div(fact(n), mul(fact(k), fact(n - k)));
}

void count_tokens(int v, int c, vector<int> const& colors, vector<vector<int>> const& neigh, vector<int>& state, int& cnt, bool& two_col, int& tokens)
{
  if (state[v] >= 0) return;
  ++cnt;
  state[v] = c;
  tokens += colors[v] ^ c;
  for (auto const& w: neigh[v]) {
    int d = 1 - c;
    if (state[w] < 0) {
      count_tokens(w, d, colors, neigh, state, cnt, two_col, tokens);
    } else if (state[w] != d) {
      two_col = false;
    }
  }
}

int solve(vector<int> const& colors, vector<vector<int>> const& neigh)
{
  int res = 1;
  int n = colors.size();
  vector<int> state(n, -1);
  for (int i = 0; i < n; ++i) {
    if (state[i] >= 0) continue;
    int cnt = 0;
    bool two_col = true;
    int tokens = 0;
    count_tokens(i, 0, colors, neigh, state, cnt, two_col, tokens);
    int cur;
    if (two_col) {
      cur = choose(cnt, tokens);
    } else {
      cur = power(2, cnt - 1);
    }
    res = mul(res, cur);
  }
  return res;
}

}

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

  int n, m;
  cin >> n >> m;
  vector<int> colors(n);
  for (auto& c: colors) {
    cin >> c;
  }
  vector<vector<int>> neigh(n);
  for (int i = 0; i < m; ++i) {
    int x, y;
    cin >> x >> y;
    neigh[x - 1].push_back(y - 1);
    neigh[y - 1].push_back(x - 1);
  }

  int res = solve(colors, neigh);
  cout << res << endl;

  return 0;
}