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#include <bits/stdc++.h>
#ifdef LOC
#include "debuglib.h"
#else
#define deb(...)
#define DBP(...)
#endif
using namespace std;
using   ll         = long long;
using   vi         = vector<int>;
using   pii        = pair<int, int>;
#define pb           push_back
#define mp           make_pair
#define x            first
#define y            second
#define rep(i, b, e) for (int i = (b); i < (e); i++)
#define each(a, x)   for (auto& a : (x))
#define all(x)       (x).begin(), (x).end()
#define sz(x)        int((x).size())

constexpr int MOD = int(1e9) + 7;

constexpr ll modPow(ll a, ll e, ll m) {
	ll t = 1 % m;
	while (e) {
		if (e % 2) t = t*a % m;
		e /= 2; a = a*a % m;
	}
	return t;
}

struct Zp {
	ll x;
	constexpr Zp() : x(0) {}
	constexpr Zp(ll a) : x(a%MOD) { if (x < 0) x += MOD; }
	#define OP(c,d) constexpr Zp& operator c##=(Zp r) { x = x d; return *this; } constexpr Zp operator c(Zp r) const { Zp t = *this; return t c##= r; }
	OP(+, +r.x - MOD*(x+r.x >= MOD));
	OP(-, -r.x + MOD*(x-r.x < 0));
	OP(*, *r.x % MOD);
	OP(/, *r.inv().x % MOD);
	constexpr Zp operator-() const { return Zp()-*this; }
	constexpr Zp inv() const { return pow(MOD-2); }
	constexpr Zp pow(ll e) const { return modPow(x,e,MOD); }
	void print() { cerr << x; }
};

vector<Zp> two, fac, facInv;
vector<vi> G;
vi state, col;
bool bip;
int siz[2], one[2];

Zp choose(int n, int k) {
	return fac[n] * facInv[k] * facInv[n-k];
}

void dfs(int v, int c) {
	if (col[v] != -1) {
		if (col[v] != c) bip = 0;
		return;
	}
	col[v] = c;
	siz[c]++;
	one[c] += state[v];
	each(e, G[v]) dfs(e, !c);
}

Zp solve(int v) {
	bip = 1;
	rep(j, 0, 2) siz[j] = one[j] = 0;
	dfs(v, 0);
	if (bip) {
		Zp ret = 0;
		rep(i, 0, siz[0]+1) {
			int j = i-one[0]+one[1];
			if (j >= 0 && j <= siz[1]) {
				ret += choose(siz[0], i) * choose(siz[1], j);
			}
		}
		return ret;
	} else {
		return two[siz[0]+siz[1]-1];
	}
}

void run() {
	int n, m;
	cin >> n >> m;

	G.assign(n, {});
	state.resize(n);
	col.resize(n, -1);

	rep(i, 0, n) {
		cin >> state[i];
	}

	rep(i, 0, m) {
		int u, v;
		cin >> u >> v;
		G[u-1].pb(v-1);
		G[v-1].pb(u-1);
	}

	two.resize(n+5, 1);
	fac.resize(n+5, 1);
	facInv.resize(n+5, 1);

	rep(i, 1, sz(two)) {
		two[i] = two[i-1] * 2;
		fac[i] = fac[i-1] * i;
		facInv[i] = fac[i].inv();
	}

	Zp ans = 1;

	rep(v, 0, n) {
		if (col[v] == -1) {
			ans *= solve(v);
		}
	}

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

int main() {
	cin.sync_with_stdio(0); cin.tie(0);
	cout << fixed << setprecision(10);
	run();
	cout << flush; _Exit(0);
}