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#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r)for(int i=(l);i<=(r);++i)
#define REP(i,n)FOR(i,0,(n)-1)
#define ssize(x)int(x.size())
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

constexpr int mod = 1'000'000'007;
int add(int a, int b) {
	a += b;
	return a >= mod ? a - mod : a;
}
int sub(int a, int b) {
	return add(a, mod - b);
}
int mul(int a, int b) {
	return int(a * LL(b) % mod);
}
int powi(int a, int b) {
	for(int ret = 1;; b /= 2) {
		if(b == 0)
			return ret;
		if(b & 1)
			ret = mul(ret, a);
		a = mul(a, a);
	}
}
int inv(int x) {
	return powi(x, mod - 2);
} // END HASH
struct BinomCoeff {
	vector<int> fac, rev;
	BinomCoeff(int n) {
		fac = rev = vector(n + 1, 1);
		FOR(i, 1, n) fac[i] = mul(fac[i - 1], i);
		rev[n] = inv(fac[n]);
		for(int i = n; i > 0; --i)
			rev[i - 1] = mul(rev[i], i);
	}
	int operator()(int n, int k) {
		if (n < 0 || k < 0 || k > n)
			return 0;
		return mul(fac[n], mul(rev[n - k], rev[k]));
	}
};

int brute(vector<vector<int>> graph, vector<int> state) {
	vector<pair<int, int>> edges;
	int n = ssize(graph);
	REP (v, n)
		for (int u : graph[v])
			if (v < u)
				edges.emplace_back(v, u);
	set<vector<int>> vis;
	function<void()> rek = [&]() {
		if (vis.count(state))
			return;
		vis.emplace(state);
		for (auto [l, r] : edges) {
			if (state[l] == state[r]) {
				state[l] ^= 1;
				state[r] ^= 1;
				rek();
				state[l] ^= 1;
				state[r] ^= 1;
			}
		}
	};
	rek();
	return ssize(vis);
}

int calc(vector<vector<int>> graph, vector<int> state) {
	int n = ssize(graph);
	vector<int> par(n), odw(n);
	function<void(int)> dfs = [&](int v) {
		odw[v] = 1;
		for (int u : graph[v])
			if (!odw[u]) {
				par[u] = par[v] ^ 1;
				dfs(u);
			}
	};
	dfs(0);
	bool ok = true;
	REP (i, n)
		for (int u : graph[i])
			if (par[i] == par[u])
				ok = false;
	if (ok) {
		bool is_moveable = false;
		REP (i, n)
			for (int u : graph[i])
				if (state[i] == state[u])
					is_moveable = true;
		if (!is_moveable)
			return 1;
		vector zli(2, vector(2, 0));
		REP (i, n)
			++zli[state[i]][par[i]];
		BinomCoeff bin(n);
		int ans = 0;
		debug(zli);
		int w = min(zli[0][0], zli[0][1]);
		zli[0][0] -= w;
		zli[0][1] -= w;
		zli[1][0] += w;
		zli[1][1] += w;
		if (zli[0][0]) {
			swap(zli[0][0], zli[0][1]);
			swap(zli[1][0], zli[1][1]);
		}
		// zli[0][0] == 0
		REP (i, min(zli[1][0], zli[1][1]) + 1) { // ile par zer
			int even = zli[0][0] + zli[1][0];
			int odd = zli[0][1] + zli[1][1];
			ans = add(ans, mul(bin(even, i), bin(odd, zli[0][1] + i)));
		}
		return ans;
		// return brute(graph, state);
	}
	else {
		vector<int> zli(2);
		REP (i, n)
			zli[state[i]] ^= 1;
		int ret = 0;
		BinomCoeff bin(n);
		for (int i = zli[0]; i <= n; i += 2)
			ret = add(ret, bin(n, i));
		return ret;
	}
}

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n, m;
	cin >> n >> m;
	vector<int> state(n);
	REP (i, n)
		cin >> state[i];
	vector<vector<int>> graph(n);
	REP (i, m) {
		int u, v;
		cin >> u >> v;
		--u;
		--v;
		graph[u].emplace_back(v);
		graph[v].emplace_back(u);
	}
	int ans = 1;
	vector<int> odw(n);
	REP (i, n) {
		if (odw[i])
			continue;
		int licz = 0;
		map<int, int> mp;
		vector<int> nstate;
		vector<vector<int>> ngraph;
		function<void(int)> dfs = [&](int v) {
			ngraph.emplace_back(vector<int>());
			nstate.emplace_back(state[v]);
			mp[v] = licz++;
			odw[v] = 1;
			for (int u : graph[v])
				if (!odw[u])
					dfs(u);
			for (int u : graph[v])
				ngraph[mp[v]].emplace_back(mp[u]);
		};
		dfs(i);
		ans = mul(ans, calc(ngraph, nstate));
	}
	cout << ans << '\n';
}