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

#define int long long
#define ll long long
#define ld long double
#define pb push_back
#define nd second
#define st first
#define sz size
#define forr(i, n) for(int i=1;i<=n;i++)
const ll infl=1e18+90;
const int inf=1e9+90;
const int roz=2e5+93;
const int mod=1e9+7;

int odw[roz], ile[2][2], xd, zap=0, tab[roz], sil[roz], odwrot[roz], kol[roz];
vector<int> graf[roz];

void dfs(int u, int o, bool x)
{
    //cerr<<"wchodze dla u = "<<u<<" x = "<<x<<"\n";
    ile[x][tab[u]]++;
    odw[u]=1;
    kol[u]=x;
    for(auto v:graf[u])
    {
        if(v==o) continue;
        if(odw[v]==0) dfs(v, u, !x);
        else if(x==kol[v]) zap=1;
    }
}

long long binpow(long long a, long long b, long long mod) {
    a %= mod;
    long long res = 1;
    while (b > 0) {
        if (b & 1)
            res = res * a % mod;
        a = a * a % mod;
        b >>= 1;
    }
    return res;
}

void silnie()
{
    sil[0]=1;
    odwrot[0]=1;
    for(int i=1;i<=roz-60;i++)
    {
        sil[i]=sil[i-1]*i;
        sil[i]%=mod;
        odwrot[i]=binpow(sil[i], mod-2, mod);
    }
}

int fun(int a, int b)
{
    //cerr<<"wchodze dla a = "<<a<<" b= "<<b<<"\n";
    //cerr<<"zwracam "<<((sil[a]*odwrot[b])%mod*odwrot[a-b])%mod<<"\n";
    return ((sil[a]*odwrot[b])%mod*odwrot[a-b])%mod;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n, m, mas=0;
    cin>>n>>m;
    silnie();
    for(int i=1;i<=n;i++)
    {
        int a;
        cin>>a;
        tab[i]=a;
    }
    for(int i=1;i<=m;i++)
    {
        int a, b;
        cin>>a>>b;
        graf[a].pb(b);
        graf[b].pb(a);
    }
    int wynik=1;
    for(int i=1;i<=n;i++)
    {
        if(odw[i]==0)
        {
            int wyn=0;
            zap=0;
            ile[0][0]=0;
            ile[1][0]=0;
            ile[0][1]=0;
            ile[1][1]=0;
            dfs(i, 0, 0);
            if(zap==1)
            {
                //cerr<<"wlazlem\n";
                int x=ile[0][0]+ile[0][1]+ile[1][0]+ile[1][1];
                int y=(ile[0][1]+ile[1][1])%2;
                for(int i=y;i<=x;i+=2)
                {
                    wyn+=fun(x, i);
                    wyn%=mod;
                }
            }
            else
            {
                //cerr<<"xd\n";
                int x=ile[0][0]+ile[0][1], y=ile[1][0]+ile[1][1];
                int z=ile[0][1], c=ile[1][1];
                //cerr<<"x = "<<x<<" y = "<<y<<" z = "<<z<<" c = "<<c<<"\n";
                while(z>0&&c>0)
                {
                    z--;
                    c--;
                }
                while(true)
                {
                    wyn+=fun(x, z)*fun(y, c);
                    wyn%=mod;
                    z++;
                    c++;
                    if(z>x) break;
                    if(c>y) break;
                }
            }
            wynik*=wyn;
            wynik%=mod;
        }
    }
    cout<<wynik<<"\n";

}