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// Karol Kosinski 2024
#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i=(a),_b=(b);i<_b;++i)
#define FR_(i,a,b) for(int i=(a),_b=(b);i<=_b;++i)
#define FD_(i,b,a) for(int i=(b),_a=(a);i>=_a;--i)
#define ALL(c) (c).begin(),(c).end()
#define SIZE(c) int((c).size())
#define X first
#define Y second
#define endl '\n'
#define NAM(x) #x,'=',x
using namespace std;
using LL = long long;
using ULL = unsigned long long;
using PII = pair<int, int>;
using TIII = tuple<int, int, int>;
template<class...T> void _cout(T...a){(cout<<...<<a);}

#ifndef ENABLE_DEBUG
#define DEB(k,p,f,x...)
#else
#define DEB(k,p,f,x...) {if(k)_cout("------",setw(4),__LINE__," : ",__FUNCTION__,endl);if(p)f(x);}
#endif
#define DEBF(f,x...)    DEB(1,1,f,x)
#define DEBL            DEBF(void,0)
#define DEBC(p,x...)    DEB(0,p,_cout,x)
#define DEBUG(x...)     DEBC(1,x)

constexpr int NX = 200'005;
constexpr LL MOD = LL(1e9) + 7;

vector<int> G[NX];
int Z[NX], D[NX];

using PLL = pair<LL, LL>;

PLL gcd_fun(LL a, LL b)
{
    if ( b == 0 ) return PLL(1, 0);
    PLL t = gcd_fun( b, a % b );
    return PLL( t.Y, t.X - ( a / b ) * t.Y );
}

LL newton(int N, int K)
{
    LL num = 1, denom = 1;
    FD_(i,N,N-K+1)
    {
        num *= i;
        num %= MOD;
    }
    FD_(i,K,1)
    {
        denom *= i;
        denom %= MOD;
    }
    LL inv = gcd_fun(MOD, denom).Y + MOD;
    inv %= MOD;
    return ( num * inv ) % MOD;
}

LL bfs(int s)
{
    int N = 0, K = 0, C[2][2] = { { 0, 0 }, { 0, 0 } };
    bool cycle = false;
    vector<int> V[2];
    queue<int> Q;
    V[ D[s] = 0 ].push_back(s);
    Q.push(s);
    while ( not Q.empty() )
    {
        ++ N;
        int u = Q.front(); Q.pop();
        for ( int v : G[u] )
        {
            if ( D[v] == -1 )
            {
                V[ D[v] = D[u] ^ 1 ].push_back(v);
                Q.push(v);
            }
            else if ( D[v] == D[u] )
            {
                cycle = true;
            }
        }
    }
    if (cycle)
    {
        LL r = 1;
        FOR(i,1,N)
        {
            r *= 2;
            r %= MOD;
        }
        return r;
    }
    FOR(i,0,2)
    {
        for ( int v : V[i] ) ++ C[i][ Z[v] ];
    }
    K += min( C[0][0], C[1][0] );
    K += min( C[0][1], C[1][1] );
    int zeroes = C[0][0] - C[1][0], ones = C[0][1] - C[1][1];
    if ( ( zeroes > 0 and ones > 0 ) or ( zeroes < 0 and ones < 0 ) )
    {
        K += min( abs(zeroes), abs(ones) );
    }
    return newton(N, K);
}

LL testcase()
{
    int n, m;
    cin >> n >> m;
    FOR(i,0,n) cin >> Z[i];
    FOR(i,0,m)
    {
        int a, b;
        cin >> a >> b;
        G[ a - 1 ].push_back( b - 1 );
        G[ b - 1 ].push_back( a - 1 );
    }
    LL res = 1;
    FOR(i,0,n) D[i] = -1;
    FOR(i,0,n)
    {
        if ( D[i] != -1 ) continue;
        res *= bfs(i);
        res %= MOD;
    }
    return res;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << testcase() << endl;
    return 0;
}