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// #pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include <bits/stdc++.h>
using namespace std;

#define PB emplace_back
#define int long long
#define ll long long
#define vi vector<int>
#define siz(a) ((int) ((a).size()))
#define rep(i, a, b) for (int i = (a); i <= (b); ++i)
#define per(i, a, b) for (int i = (a); i >= (b); --i)
void print(vi n) { rep(i, 0, siz(n) - 1) cerr << n[i] << " \n"[i == siz(n) - 1]; }

const int N = 4e5, mod = 1e9 + 7;
int a, b, s[N + 5], fa[N + 5], p[N + 5][2];
bool vis[N + 5], is[N + 5];
vi st[N + 5];
int fac[N + 5], inv[N + 5];
int qp(int n, int m = mod - 2) {
	int res = 1;
	for (; m; m >>= 1) {
		if (m & 1) res = res * n % mod;
		n = n * n % mod;
	}
	return res;
}
void init() {
	fac[0] = fac[1] = 1;
	rep(i, 2, N) fac[i] = fac[i - 1] * i % mod;
	inv[N] = qp(fac[N]);
	per(i, N - 1, 0) inv[i] = inv[i + 1] * (i + 1) % mod;
}
int C(int n, int m) {return fac[n] * inv[m] % mod * inv[n - m] % mod;}

int f(int n) {return fa[n] == n ? n : fa[n] = f(fa[n]);}

signed main() {
	// freopen(".in", "r", stdin);
	// freopen(".out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	init();
	cin >> a >> b;
	rep(i, 1, a) cin >> s[i], fa[i] = i, fa[i + a] = i + a, p[i][s[i]] = 1;
	int x, y;
	rep(i, 1, b) {
		cin >> x >> y;
		if(f(x) != f(y + a)) {
			p[f(y + a)][0] += p[f(x)][0];
			p[f(y + a)][1] += p[f(x)][1];
			is[f(y + a)] |= is[f(x)];
			fa[f(x)] = f(y + a);
		}
		if(f(y) != f(x + a)) {
			p[f(x + a)][0] += p[f(y)][0];
			p[f(x + a)][1] += p[f(y)][1];
			is[f(x + a)] |= is[f(y)];
			fa[f(y)] = f(x + a);
		}
		if(s[x] == s[y]) is[f(x)] = is[f(y)] = 1;
	}
	int ans = 1;
	rep(i, 1, a) if(!vis[f(i)]) {
		vis[f(i)] = vis[f(i + a)] = 1;
		// cout << i << endl;
		if(!is[f(i)]) continue;
		if(f(i) == f(i + a)) {
			int siz = p[f(i)][0] + p[f(i)][1], tmp = 0;
			rep(j, 0, siz) if((j & 1) == (p[f(i)][0] & 1)) {
				// cout << j << endl;
				(tmp += C(siz, j)) %= mod;
			}
			(ans *= tmp) %= mod;
		}
		else {
			int s1 = p[f(i)][0] + p[f(i)][1], s2 = p[f(i + a)][0] + p[f(i + a)][1], tmp = 0;
			rep(x, 0, s1) {
				int y = x - p[f(i)][0] + p[f(i + a)][0];
				if(y < 0 || y > s2) continue;
				(tmp += C(s1, x) * C(s2, y)) %= mod;
			}
			(ans *= tmp) %= mod;
		}
	}
	cout << ans;
	return cerr << endl << 1.0 * clock() / CLOCKS_PER_SEC << endl, 0;
}