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

#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) 42
#endif

#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)

#define rep(i, n) for (int i = 0; i < (n); ++i)
#define repp(i, n, m) for (int i = (n); i < (m); ++i)

#define repr(i, n) for (int i = (n) - 1; i >= 0; --i)
#define reppr(i, n, m) for (int i = (m) - 1; i >= (n); --i)

#define each(a,x) for(auto& a : (x))
#define sz(x) int((x).size())

using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using pi = pair<int, int>;
using pll = pair<ll, ll>;

template <typename T, typename V> void mini(T& a, V b) {if (b < a) a = b; }
template <typename T, typename V> void maxi(T& a, V b) {if (b > a) a = b; }

const int P = 1e9 + 7, phiP = P - 1;
struct modint {
    int x = 0;
    modint operator+(modint o) const {return {x + o.x >= P ? x + o.x - P : x + o.x}; }
    modint operator-(modint o) const {return {x < o.x ? x - o.x + P : x - o.x}; }
    modint operator+() const {return *this; }
    modint operator-() const {return {x ? P - x : 0}; }
    modint operator*(modint o) const {return {int(ll(x) * o.x % P)}; }
    modint operator/(modint o) const {return *this * o.inv(); }
    modint & operator+=(modint o) {return *this = *this + o; }
    modint & operator-=(modint o) {return *this = *this - o; }
    modint & operator*=(modint o) {return *this = *this * o; }
    modint & operator/=(modint o) {return *this = *this / o; }
    modint pow(ll e) const {
        modint ret{1}, b(*this);
        for (; e; e >>= 1) {
            if (e & 1)
                ret *= b;
            b *= b;
        }
        return ret;
    }
    modint inv() const {return pow(phiP - 1); }
    friend void __dbg(modint m) {
        cout << m.x - P * (2 * m.x >= P);
    }
};

vector<modint> fact = {modint{1}}, ifact = {modint{1}};

vvi g;
vi on, vis;

void dfs(int v, int col, array<array<int, 2>, 2> &counts, bool &twocol) {
    if (vis[v] == (col ^ 1))
        twocol = false;
    if (vis[v] != -1)
        return;
    vis[v] = col;
    ++counts[col][on[v]];
    for (int j : g[v])
        dfs(j, col ^ 1, counts, twocol);
}

void solve() {
    rep(_, 3e5) {
        fact.push_back(fact.back() * modint{sz(fact)});
        ifact.push_back(fact.back().inv());
    }

    int n, m;
    cin >> n >> m;
    on.resize(n);
    vis.resize(n, -1);
    g.resize(n);
    rep(i, n)
        cin >> on[i];
    rep(_, m) {
        int a, b;
        cin >> a >> b;
        --a; --b;
        g[a].push_back(b);
        g[b].push_back(a);
    }

    modint ans{1};

    rep(i, n) {
        if (vis[i] != -1)
            continue;
        array<array<int, 2>, 2> counts{}; // [kolor][czy on]
        bool twocol = true;
        dfs(i, 0, counts, twocol);

        debug(i, twocol, counts);

        int ile = counts[0][0] + counts[0][1] + counts[1][0] + counts[1][1];

        if (!twocol) {
            ans *= modint{2}.pow(ile - 1);
            continue;
        }

        modint here;

        for (int add = -ile; add <= ile; ++add) {
            if (add > counts[0][0])
                continue;
            if (add > counts[1][0])
                continue;
            if (add + counts[0][1] < 0)
                continue;
            if (add + counts[1][1] < 0)
                continue;

            here += fact[counts[0][0] + counts[0][1]] * ifact[counts[0][0] - add] * ifact[counts[0][1] + add] *
                    fact[counts[1][0] + counts[1][1]] * ifact[counts[1][0] - add] * ifact[counts[1][1] + add];
        }

        ans *= here;
    }

    cout << ans.x << '\n';
}


int main() {
#ifdef DEBUG
    const int MEMSIZE = 1024 * 1024 * 1024;
    static_assert(MEMSIZE % 16 == 0);
    static char stack[MEMSIZE];
    asm volatile (
        "mov %[newstack], %%rsp\n"
        "call *%[funcptr]"
        :: [funcptr] "r" (solve), [newstack] "r" (stack + MEMSIZE)
    );
    exit(0);
#else
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    solve();
#endif
}