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#pragma GCC optimize ("Ofast")
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define FOR(i, a, b) for (auto i=(a); i<(b); i++)
#define FORD(i, a, b) for (int i=(a); i>(b); i--)
#define SZ(x) ((int)(x).size())
#define ALL(x) (x).begin(), (x).end()
#define PPC(x) __builtin_popcountll(x)
#define MSB(x) (63 - __builtin_clzll(x))
#define LSB(x) __builtin_ctzll(x)
#define ARG(x, i) (get<i>(x))
#define ithBit(m, i) ((m) >> (i) & 1)
#define pb push_back
#define ft first
#define sd second
#define kw(a) ((a) * (a))
#define CLR(x) x.clear(), x.shrink_to_fit()
#ifdef DEBUG
#include "debug.h"
#else
#define dbg(...) 0
#endif
using namespace std;
 
template <typename T1, typename T2> inline void remin(T1& a, T2 b) { a = min(a, (T1)b);	}
template <typename T1, typename T2> inline void remax(T1& a, T2 b) { a = max(a, (T1)b);	}

const int maxN = 1 << 18, mod = 1'000'000'007;

template <typename T1, typename T2> inline void addMod(T1& a, T2 b) { a = (a + b) % mod; }
template <typename T1, typename T2> inline void multMod(T1& a, T2 b) { a = a * b % mod; }

long long qpow(long long a, long long b)
{
	long long ret = 1ll;
	for (; b != 0; b /= 2)
	{
		if (b & 1)	multMod(ret, a);
		multMod(a, a);
	}
	return ret;
}

template <typename T1, typename T2> inline void subMod(T1& a, T2 b) { a = (a - b%mod + mod) % mod; }
template <typename T1, typename T2> inline void divMod(T1& a, T2 b) { a = a * qpow(b, mod-2) % mod; }

long long fact[maxN], tcaf[maxN], pow2[maxN];

long long cf(int n, int k)
{
	static bool initd = false;
	if (!initd)
	{
		fact[0] = tcaf[0] = 1ll;
		FOR(i, 1, maxN)	fact[i] = fact[i-1] * i % mod;
		tcaf[maxN-1] = qpow(fact[maxN-1], mod-2);
		FORD(i, maxN-1, 0)	tcaf[i-1] = tcaf[i] * i % mod;
		initd = true;
	}
	
	if (k < 0 or k > n)	return 0;
	long long ret = fact[n];
	multMod(ret, tcaf[k]);
	multMod(ret, tcaf[n-k]);
	return ret;
}

bool vis[maxN];
int myColor[maxN], C[maxN];
int compSz, k;
bool oddCycle;

vector <int> G[maxN];

void dfs(int v)
{
	vis[v] = true;
	compSz++;
	k += myColor[v] != C[v];

	for (int u : G[v])
	{
		if (vis[u])
		{
			if (myColor[v] == myColor[u])
				oddCycle = true;
		}
		else
		{
			myColor[u] = myColor[v] ^ 1;
			dfs(u);
		}
	}
}

void solve()
{
	int n, m;
	scanf ("%d%d", &n, &m);
	pow2[0] = 1ll;

	FOR(i, 1, n+1)
		scanf ("%d", C+i), pow2[i] = pow2[i-1] * 2 % mod;

	while (m--)
	{
		int a, b;
		scanf ("%d%d", &a, &b);
		G[a].pb(b);
		G[b].pb(a);
	}

	long long res = 1;
	FOR(i, 1, n+1) if (!vis[i])
	{
		dfs(i);
		long long resLocal = 1;

		if (oddCycle)
			resLocal = pow2[compSz - 1];
		else
			resLocal = cf(compSz, k);

		multMod(res, resLocal);

		k = compSz = 0;
		oddCycle = false;		
	}
	printf("%lld\n", res);
}

int main()
{
	int t = 1;
//	scanf ("%d", &t);	
	FOR(tid, 1, t+1)
	{
		//printf("Case #%d: ", tid);
		solve();
	}
	return 0;
}