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#include <bits/stdc++.h>

#define pb push_back

using namespace std;

typedef vector<int> vi;
typedef pair<int, int> pii;

const int mod = 1e9+7;
const int N = 200003;
bool visited[N];
bool visited2[N];
bool color[N];
vi adj[N];
bool stan[N];
vector<long long> pot2;
vector<long long> sil;
int rozmiar;
int odd_jed, odd;
int even_jed, even;

long long odw(long long a) {
    long long w = mod-2;
    long long p = a;
    long long ans = 1;
    while(w) {
        if(w%2) ans = (ans*p) % mod;
        w /= 2;
        p = (p*p) % mod;
    }
    return ans;
}

long long dwu(int n, int k) {
    if(k > n  ||  k < 0) return 0;
    long long L = sil[n];
    long long M = (sil[k]*sil[n-k]) % mod;
    return (L*odw(M)) % mod;
}


bool dfs(int x) {
    //cout << "* " << x << " *";
    
    if(color[x]) {
        odd++;
        if(stan[x]) odd_jed++;
    }
    else {
        even++;
        if(stan[x]) even_jed++;
    }
    
    
    for(auto u : adj[x]) {
        if(!visited[u]) {
            visited[u] = true;
            color[u] = !color[x];
            if(!dfs(u)) return false;
        }
        else if(color[x] == color[u]) return false;
    }
    
    return true;
}

void dfs2(int x) {
    if(visited2[x]) return;
    visited2[x] = true;
    visited[x] = true;
    rozmiar++;
    
    for(auto u : adj[x]) {
        dfs2(u);
    }
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);	
    

    int n, m;
    cin >> n >> m;
    
    pot2.pb(1);
    sil.pb(1);
    for(long long i = 1; i <= N; i++) {
        long long k = pot2.back();
        pot2.pb((2*k)%mod);
        long long s = sil.back();
        sil.pb((i*s)%mod);
    }
    
    
    for(int i = 1; i <= n; i++) {
        int k; cin >> k;
        stan[i] = k;
    }
    
    for(int i = 0; i < m; i++) {
        int a, b;
        cin >> a >> b;
        adj[a].pb(b);
        adj[b].pb(a);
    }
    //
    
    long long ans = 1;
    for(int i = 1; i <= n; i++) {
        if(visited[i]) continue;
        rozmiar = 0;
        odd_jed = odd = 0;
        even_jed = even = 0; 
        
        color[i] = 1;
        visited[i] = true;
        bool bip = dfs(i);
        if(!bip) {
            dfs2(i);
            //cout << " bip ";
            ans = (ans * pot2[rozmiar-1]) % mod;
        }
        else {
            int r = odd_jed - even_jed;
            //cout << " odd_jed: " << odd_jed << " odd: " << odd << " even_jed: " << even_jed << " even: " << even << "\n";
            long long count = 0;
            for(int k = -r; k <= odd - r; k++) {
                long long plus = ( dwu(odd, k+r) * dwu(even, k) ) % mod;
                count = (count + plus) % mod;
            }
            ans = (ans * count) % mod;
        }
        
        //cout << ans << " new\n";
    }
    
    cout << ans << "\n";
    
	
    return 0;
}