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#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> PII;
typedef pair<long long,int> PLI;
typedef pair<int,long long> PIL;
const int mod = 1e9+7;

vector<int> G[200005];
int col[200005];
int side[200005];

bool is_bip = true;
vector<int> vertices;
void dfs(int v){
    vertices.push_back(v);
    for(int u: G[v]){
        if(side[u] != -1){
            if(side[u] == side[v]) is_bip = false;
        }
        else{
            side[u] = 1-side[v];
            dfs(u);
        }
    }
}

long long fact[200005];
long long rfact[200005];

long long pot(long long a, long long x){
    if(x == 0) return 1;
    if(x&1) return pot(a, x-1)*a%mod;
    long long tmp = pot(a, x/2);
    return tmp*tmp%mod;
}

long long binom(int n, int k){
    long long res = fact[n]*rfact[k]%mod;
    res = res*rfact[n-k]%mod;
    return res;
}

int main(){
    ios_base::sync_with_stdio(0);
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;i++) cin>>col[i];
    for(int i=0;i<m;i++){
        int a,b;
        cin>>a>>b;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    
    for(int i=1;i<=n;i++) side[i] = -1;

    fact[0] = 1;
    for(int i=1;i<=n;i++) fact[i] = fact[i-1]*i%mod;
    for(int i=0;i<=n;i++) rfact[i] = pot(fact[i], mod-2);

    long long res = 1;
    for(int i=1;i<=n;i++){
        if(side[i] != -1) continue;
        side[i] = 0;
        dfs(i);
        if(is_bip){
            int cnt_black[2] = {0, 0};
            int cnt[2] = {0, 0};
            for(int v: vertices){
                if(col[v] == 1){
                    cnt_black[side[v]]++;
                }
                cnt[side[v]]++;
            }
            if(cnt_black[0] < cnt_black[1]){
                swap(cnt_black[0], cnt_black[1]);
                swap(cnt[0], cnt[1]);
            }

            long long tmp = 0;
            for(int k=cnt_black[0]-cnt_black[1];k<=cnt[0];k++){
                int s = k-(cnt_black[0]-cnt_black[1]);
                if(s > cnt[1]) continue;
                // cout<<cnt[0]<<" "<<cnt[1]<<" "<<cnt_black[0]<<" "<<cnt_black[1]<<" "<<k<<" "<<s<<" "<<binom(cnt[0], k)<<" "<<binom(cnt[1], s)<<endl;
                tmp = (tmp+binom(cnt[0], k)*binom(cnt[1], s))%mod;
            }
            res = (res*tmp)%mod;
        }
        else{
            // cout<<" "<<vertices.size()<<endl;
            for(int j=1;j<vertices.size();j++) res = (res*2)%mod;
        }
        is_bip = true;
        vertices.clear();
    }

    cout<<res<<endl;
}