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#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define int long long
#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define rep(i,a,b) for(ll i=(ll)a;i<=(ll)b;++i)
#define all(a) a.begin(),a.end()
#define sz(x) (int)(x).size()
const int mxN = 2e5+7, mod = 1e9+7;
vector<int> graf[mxN];
bool a[mxN];
int c[mxN];
int cnt[2][2];

bool dfs(int v,int pop){
    c[v] = pop;
    cnt[pop][a[v]]++;
    bool res = 1;
    for(auto u : graf[v]){
        if(c[v] == c[u]) res = 0;
        if(c[u] == -1) res &= dfs(u, pop^1);
    }
    return res;
}

template<typename T>
struct Newton{
    int n;
    vector<T> frac, rfrac;
    Newton(int n_) : n(n_), frac(n_+1), rfrac(n_+1) {}
    
    T InverseMod(T a, T w = mod-2){
        T res = 1;
        while(w){
            if(w&1) res = (res * a)%mod;
            a = (a*a)%mod;
            w /= 2;
        }
        return res;
    }

    void prep(){
        frac[0] = 1;
        for(int i=1;i<=n;i++) frac[i] = (frac[i-1]*i) % mod;
        rfrac[n] = InverseMod(frac[n]);
        for(int i=n-1;i>=0;i--) rfrac[i] = (rfrac[i+1]*(i+1)) % mod;
    }

    T choose(T a, T b){
        if(b > a) return 0;
        return (((frac[a]*rfrac[b])%mod)*rfrac[a-b])%mod;
    }
};


int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n,m; cin >> n >> m;
    rep(i,1,n) cin >> a[i];
    while(m--){
        int u,v; cin >> u >> v;
        graf[u].pb(v);
        graf[v].pb(u);
    }
    rep(i,1,n) c[i] = -1;
    int res = 1;

    Newton<int> C(n+7);
    C.prep();

    rep(i,1,n) if(c[i] == -1){
        rep(x,0,1) rep(y,0,1) cnt[x][y] = 0;
        bool b = dfs(i, 0);

        if(b){
            int akt = 0;
            while(cnt[0][0] >= 1 && cnt[1][0] >= 1){
                cnt[0][0]--;
                cnt[0][1]++;
                cnt[1][0]--;
                cnt[1][1]++;
            }

            while(cnt[0][1] >= 0 && cnt[1][1] >= 0){
                akt = (akt+(C.choose(cnt[0][0]+cnt[0][1], cnt[0][0])*C.choose(cnt[1][0]+cnt[1][1], cnt[1][0]))%mod)%mod;
                cnt[0][0]++;
                cnt[0][1]--;
                cnt[1][0]++;
                cnt[1][1]--;
            }
            res = (res*akt)%mod;

        }else{
            int akt = 0;
            rep(x,0,1) cnt[0][x] += cnt[1][x];
            while(cnt[0][0] >= 2){
                cnt[0][0] -= 2;
                cnt[0][1] += 2;
            }

            while(cnt[0][1] >= 0){
                akt = (akt+C.choose(cnt[0][0]+cnt[0][1], cnt[0][0]))%mod;
                cnt[0][0] += 2;
                cnt[0][1] -= 2;
            }
            res = (res*akt)%mod;

        }   
    }
    cout << res << "\n";
}