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// clang-format off
#pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
using namespace std;
template<class Fun>
class y_combinator_result {
    Fun fun_;
public:
    template<class T> explicit y_combinator_result(T &&fun): fun_(forward<T>(fun)) {}
    template<class ...Args> decltype(auto) operator()(Args &&...args) { return fun_(ref(*this), forward<Args>(args)...); }
};
template<class Fun> decltype(auto) y_combinator(Fun &&fun) { return y_combinator_result<decay_t<Fun>>(forward<Fun>(fun)); }
// using namespace __gnu_pbds;
// template <typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef XOX
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) { ris << "(" << d.first << ", " << d.second << ")"; }
sim dor(rge<c> d) { *this << "["; for (auto it = d.b; it != d.e; ++it) *this << ", " + 2 * (it == d.b) << *it; ris << "]"; }
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
struct { template <class T> operator T() { T x; cin >> x; return x; } } in;
#define endl '\n'
#define pb emplace_back
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
using i64 = long long;
template <class T> using vt = vector<T>;
template <class T, size_t n> using ar = array<T, n>;
namespace R = ranges;
auto ra(auto x, auto y) { return R::iota_view(x, y); }
auto rae(auto x, auto y) { return ra(x, y + 1); }
// #define int long long
template <class T>
T power(T a, i64 b) { T res = 1; for (; b; b /= 2, a *= a) if (b % 2) res *= a; return res; }
template <int P>
struct MInt {
    int x;
    MInt() : x{} {}
    MInt(i64 _x) : x{norm(_x % P)} {}
    int norm(int _x) const { if (_x < 0) _x += P; if (_x >= P) _x -= P; return _x; }
    int val() const { return x; }
    explicit operator int() const { return x; }
    MInt operator-() const { MInt res; res.x = norm(P - x); return res; }
    MInt inv() const { assert(x != 0); return power(*this, P - 2); }
    MInt &operator*=(MInt rhs) { x = (i64)x * rhs.x % P; return *this; }
    MInt &operator+=(MInt rhs) { x = norm(x + rhs.x); return *this; }
    MInt &operator-=(MInt rhs) { x = norm(x - rhs.x); return *this; }
    MInt &operator/=(MInt rhs) { return *this *= rhs.inv(); }
    friend MInt operator*(MInt lhs, MInt rhs) { MInt res = lhs; res *= rhs; return res; }
    friend MInt operator+(MInt lhs, MInt rhs) { MInt res = lhs; res += rhs; return res; }
    friend MInt operator-(MInt lhs, MInt rhs) { MInt res = lhs; res -= rhs; return res; }
    friend MInt operator/(MInt lhs, MInt rhs) { MInt res = lhs; res /= rhs; return res; }
    friend istream &operator>>(istream &is, MInt &a) { i64 v; is >> v; a = MInt(v); return is; }
    friend ostream &operator<<(ostream &os, const MInt &a) { return os << a.val(); }
    friend bool operator==(MInt lhs, MInt rhs) { return lhs.val() == rhs.val(); }
    friend bool operator!=(MInt lhs, MInt rhs) { return lhs.val() != rhs.val(); }
};
const int P = 1000 * 1000 * 1000 + 7;
using Z = MInt<P>;
struct Comb {
    int n;
    vector<Z> _fac;
    vector<Z> _invfac;
    vector<Z> _inv;
    Comb() : n{0}, _fac{1}, _invfac{1}, _inv{0} {}
    Comb(int _n) : Comb() { init(_n); }
    void init(int m)
    {
        if (m <= n) return;
        _fac.resize(m + 1);
        _invfac.resize(m + 1);
        _inv.resize(m + 1);
        for (int i = n + 1; i <= m; i++)
            _fac[i] = _fac[i - 1] * i;
        _invfac[m] = _fac[m].inv();
        for (int i = m; i > n; i--) {
            _invfac[i - 1] = _invfac[i] * i;
            _inv[i] = _invfac[i] * _fac[i - 1];
        }
        n = m;
    }
    Z fac(int m) { if (m > n) init(2 * m); return _fac[m]; }
    Z invfac(int m) { if (m > n) init(2 * m); return _invfac[m]; }
    Z binom(int _n, int m) { if (_n < m || m < 0) return 0; return fac(_n) * invfac(m) * invfac(_n - m); }
} comb;
// clang-format on

void solve() {
    int n = in, m = in;
    vt<bool> v;
    for (int i : ra(0, n)) {
        int x = in;
        v.pb(x);
    }
    vt<vt<int>> g(n);
    for (int i : ra(0, m)) {
        int a = in, b = in;
        --a, --b;
        g[a].pb(b);
        g[b].pb(a);
    }
    vt<int> col(n, -1);
    vt<int> spo;
    auto work = [&](int u) -> bool {
        queue<int> q;
        q.push(u);
        col[u] = 0;
        bool ok = true;
        spo.clear();
        while (!q.empty()) {
            int u = q.front();
            q.pop();
            spo.pb(u);
            for (int to : g[u]) {
                if (col[to] == -1) {
                    col[to] = col[u] ^ 1;
                    q.push(to);
                } else {
                    ok &= col[to] != col[u];
                }
            }
        }
        return ok;
    };
    Comb comb;
    Z ans = 1;
    for (int i : ra(0, n)) {
        if (col[i] == -1) {
            if (!work(i)) {
                ans *= power(Z(2), sz(spo) - 1);
            } else {
                if (sz(spo) == 1) continue;
                int kurdebele = 0;
                ar<int, 2> c{0, 0};
                for (int j : spo) {
                    if (v[j] == 1) kurdebele += (col[j] ? +1 : -1);
                    c[col[j]]++;
                }
                Z sum = 0;
                for (int l = 0; l <= c[1]; l++) {
                    int r = l - kurdebele;
                    if (r >= 0 && r <= c[0]) sum += comb.binom(c[1], l) * comb.binom(c[0], r);
                }
                ans *= sum;
            }
        }
    }
    cout << ans << endl;
}

int32_t main() {
    cin.tie(0)->sync_with_stdio(0);
    int t = 1;
    // int t = in;
    while (t--) {
        solve();
    }
}