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#include <bits/stdc++.h>

using namespace std;

#define st first
#define nd second
typedef long long ll;
typedef long double ld;
typedef __int128 int128;
typedef vector<int> vi;
typedef pair<int,int> pi;
typedef pair<double,double> pd;
typedef pair<ll,ll> pl;

const int max_n = 2e5+7;
const ll mod = 1e9+7;

bool on[max_n];
bool odw[max_n];
vi g[max_n];

int ile[max_n];
pi rodzaj[max_n];
bool color[max_n];
bool check[max_n];
bool dobry[max_n];

ll power[max_n];
ll fact[max_n];

ll pow(ll x, ll a){
    if(a == 1) return x;

    ll prev = pow(x,a/2);
    ll akt = (prev*prev)%mod;
    if(a%2 == 1) akt = (akt*x)%mod;

    return akt;
}

ll get_inverse(ll a, ll b){
    return (a*pow(b,mod-2))%mod;
}

void dfs(int v, int num){
    //odw[v] = 1;
    ile[num]++;
    //cout << "v: " << v << " num: " << num << '\n';
    if(color[v]) rodzaj[num].st++;
    else rodzaj[num].nd++;

    for(auto x:g[v]){
        if(on[v] == on[x]) check[num] = 1;
        if(odw[x]){
            if(color[v] == color[x]) dobry[num] = 1;
            continue;
        }
        color[x] = !color[v];
        odw[x] = 1;
        dfs(x,num);
    }
}

int main(){

    ios::sync_with_stdio(0);
    cin.tie(0);

    int n,m;
    cin >> n >> m;

    power[0] = 1;
    fact[0] = 1;
    for(ll i = 1; i <= n; i++){
        power[i] = (power[i-1]*2LL)%mod;
        fact[i] = (fact[i-1]*i)%mod;
    }

    for(int i = 1; i <= n; i++) cin >> on[i];

    for(int i = 1; i <= m; i++){
        int a,b;
        cin >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }

    int akt_s = 0;
    for(int i = 1; i <= n; i++){
        if(!odw[i]){
            odw[i] = 1;
            dfs(i,++akt_s);
        }
    }

    ll ans = 1;
    for(int i = 1; i <= akt_s; i++){
        //cout << "i: " << i << " ile: " << ile[i] 
        //     << " check: " << check[i] << " dobry: " << dobry[i] << '\n';
        if(!check[i]) continue;
        ll val = power[ile[i]-1];
        //cout << "first val: " << val << '\n';
        if(!dobry[i] && ile[i] > 2){
            ll a = rodzaj[i].st;
            ll b = rodzaj[i].nd;
            if(a < b) swap(a,b);

            //cout << "a: " << a << " b: " << b << '\n';

            val = 1;
            for(int i = 1; i <= b; i++){
                ll up = (fact[a]*fact[b])%mod;
                ll down = (fact[i]*fact[i])%mod;
                down *= (fact[a-i]*fact[b-i])%mod;
                down %= mod; 
                //cout << "i: " << i << " up: " << up << " down: " << down << '\n';
                val += get_inverse(up,down);
            }
        }
        //cout << "val: " << val << "\n";
        ans *= val;
        ans %= mod;
    }

    cout << ans << '\n';

    return 0;
}

//g++ -O3 -static -Wall .cpp -std=c++17