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

#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define REP(i, n) for(int i = 0; i < (n); ++i)

template<class T> int ssize(T && a) {
	return (int)(a.size());
}
ostream& operator << (ostream &os, string str) {
    for(char c : str) os << c;
    return os;
}
template <class A, class B> ostream& operator << (ostream &os, const pair<A, B> &p) {
	return os << '(' << p.first << "," << p.second << ')';
}
template <class T> auto operator << (ostream &os, T &&x) -> decltype(x.begin(), os) {
	os << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		os << *it << (it == prev(x.end()) ? "" : " ");
	return os << '}';
}
template <class T> ostream& operator << (ostream &os, vector<vector<T>> vec) {
    for(auto x : vec)
    	os << "\n  " << x;
    return os;
}
void dump() {}
template <class T, class... Args> void dump(T &&x, Args... args) {
    cerr << x << "; ";
    dump(args...);
}
#ifdef DEBUG
# define debug(x...) cerr << "[" #x "]: ", dump(x), cerr << '\n'
#else 
# define debug(...) 0
#endif

//--------------------------------------------------

//https://github.com/tonowak/acmlib
using LL = long long;
template<int mod>
struct modular {
	int val;
	modular() { val = 0; }
	modular(const LL& v) {
		val = int((-mod <= v && v < mod) ? (int) v : v % mod);
		if(val < 0) val += mod;
	}
	int to_int() { return val; }
	friend ostream& operator<<(ostream &os, const modular &a) {
#ifdef DEBUG
		constexpr int mx = 1024;
		for(int y = 1; y <= mx; ++y)
			if(a * y <= mx)
				return os << (a * y).val << '/' << y;
			else if(mod - a * y <= mx)
				return os << '-' << (mod - a * y).val << '/' << y;
#endif
		return os << a.val;
	}
	friend istream& operator>>(istream &is, modular &a) {
		return is >> a.val;
	}
	friend bool operator==(const modular &a, const modular &b) {
		return a.val == b.val;
	}
	friend bool operator!=(const modular &a, const modular &b) {
		return !(a == b);
	}
	friend bool operator<(const modular &a, const modular &b) {
		return a.val < b.val;
	}
	friend bool operator<=(const modular &a, const modular &b) {
		return a.val <= b.val;
	}
	modular operator-() const { return modular(-val); }
	modular& operator+=(const modular &m) {
		if((val += m.val) >= mod) val -= mod;
		return *this;
	}
	modular& operator-=(const modular &m) {
		if((val -= m.val) < 0) val += mod;
		return *this;
	}
	modular& operator*=(const modular &m) {
		val = int((LL) val * m.val % mod);
		return *this;
	}
	friend modular qpow(modular a, LL n) {
		if(n == 0) return 1;
		if(n % 2 == 1) return qpow(a, n - 1) * a;
		return qpow(a * a, n / 2);
	}
	friend modular inv(const modular &a) {
		assert(a != 0); return qpow(a, mod - 2);
	}
	modular& operator/=(const modular &m) {
		return (*this) *= inv(m);
	}
	modular operator++(int) {
		modular res = (*this);
		(*this) += 1;
		return res;
	}
	friend modular operator+(modular a, const modular &b) { return a += b; }
	friend modular operator-(modular a, const modular &b) { return a -= b; }
	friend modular operator*(modular a, const modular &b) { return a *= b; }
	friend modular operator/(modular a, const modular &b) { return a /= b; }
};
using mint = modular<int(1e9 + 7)>;
// using mint = modular<998244353>;
struct BinomCoeff {
	vector<mint> fac, rev;
	BinomCoeff(int n) {
		fac = rev = vector<mint>(n + 1, 1);
		FOR(i, 1, n) fac[i] = fac[i - 1] * i;
		rev[n] = 1 / fac[n];
		for(int i = n; i >= 1; i--)
			rev[i - 1] = rev[i] * i;
	}
	mint operator()(int n, int k) {
		return fac[n] * rev[n - k] * rev[k];
	}
};

vector<int> color;
vector<vector<int>> graph;

int n, m;
vector<int> c;

vector<int> component;
void color_dfs(int u) {
	component.emplace_back(u);
	if (color[u] == -1) color[u] = 0;

	for (int v : graph[u]) {
		if (color[v] == -1) {
			color[v] = color[u] ^ 1;
			color_dfs(v);
		}
	}
}

bool biparite(int source) {
	component.clear();
	color_dfs(source);

	for (int u : component) {
		for (int v : graph[u]) {
			if (color[u] == color[v])
				return false;
		}
	}

	return true;
}

vector<int> match, visited;
int t = 0, matching_size = 0;
bool matching_dfs(int v) {
	visited[v] = t;
	for(int u : graph[v]) if (c[u] == c[v]) {
		if(match[u] == -1) {
			match[u] = v;
			match[v] = u;
			return true;
		}
	}

	for(int u : graph[v]) if (c[u] == c[v]) {
		if(visited[match[u]] != t && matching_dfs(match[u])) {
			match[u] = v;
			match[v] = u;
			return true;
		}
	}

	return false;
}

int turbo_matching() {
	matching_size = 0;
	int d = -1;
	while(d != 0) {
		d = 0, ++t;
		for (int u : component)
			if(match[u] == -1)
				d += matching_dfs(u);
		matching_size += d;
	}

	return matching_size;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	cin >> n >> m;

	c = vector<int>(n, 0);
	int source = 0;
	REP (i, n) {
		cin >> c[i];
		if (c[i]) source |= (1 << i);
	}

	graph.resize(n);
	REP (i, m) {
		int a, b;
		cin >> a >> b;
		--a, --b;

		graph[a].emplace_back(b);
		graph[b].emplace_back(a);
	}

	match = visited = color = vector<int>(n, -1);

	BinomCoeff C(n + 1);

	mint answer = 1;
	REP (u, n) {
		if (color[u] == -1) {
			if (!biparite(u)) {
				mint ret = qpow(mint(2), ssize(component) - 1);
				answer *= ret;

				debug(ret);
			} else {
				bool active = false;
				array<int, 2> left = {0, 0}, right = {0, 0};
				for (int v : component) {
					if (color[v] == 0) 
						left[c[v]]++;
					else right[c[v]]++;

					for (int w : graph[v]) {
						if (c[v] == c[w]) {
							active = true;
						} 
					}
				}

				if (!active) continue;

				if (left[0] + left[1] > right[0] + right[1])
					swap(left, right);

				debug(left);
				debug(right);

				int k = 0;
				REP (b, 2) {
					if (left[b] > right[b]) continue;

					int take = min(left[b], right[b]);
					int ans = right[b ^ 1] + take;
					k = max(ans, k);
				}

				debug(component, k);
				mint ret = C(ssize(component), k);
				answer *= ret;

				debug(ret);
			}
		}
	}

	cout << answer << '\n';
}