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#include<cstdio>
#include<algorithm>
#include<vector>
#define S 200007

using namespace std;
typedef long long ll;
ll mod = 1000000007;

vector<int> V[S];
int T[S];

int color[S];
bool vis[S];
vector<int> P;

void DFS(int x){
    vis[x] = 1;
    P.push_back(x);
    for(int i = 0; i < V[x].size(); i++){
        int v = V[x][i];
        if(!vis[v]){
            color[v] = color[x] ^ 1;
            DFS(v);
        }
    }
}

ll pot(ll x, ll y){
    if(y == 0)
        return 1;
    if(y == 1)
        return x;
    if(y % 2 == 0){
        ll p = pot(x,y/2);
        return (p*p)%mod;
    }else{
        return (pot(x,y-1) * x)%mod;
    }
}

ll sil[S];

ll f(int x, int y){
    ll p = sil[x];
    ll p2 = sil[y] * sil[x-y];
    p2 %= mod;
    p2 = pot(p2, mod-2);
    p *= p2;
    p %= mod;
    return p;
}

int main(void){
    sil[0] = 1;
    for(int i = 1; i < S; i++){
        sil[i] = sil[i-1] * i;
        sil[i] %= mod;
    }
    int n,m;
    scanf("%d %d",&n,&m);
    for(int i = 1; i <= n; i++){
        scanf("%d", &T[i]);
    }

    for(int i = 1; i <= m; i++){
        int a,b;
        scanf("%d %d",&a,&b);
        V[a].push_back(b);
        V[b].push_back(a);
    }

    ll ans = 1;

    for(int i = 1; i <= n; i++){
        if(!vis[i]){
            
            P.clear();

            DFS(i);

            bool cycle = false;
            bool good = false;

            int b1 = 0;
            int b2 = 0;
            int c1 = 0;
            int c2 = 0;

            for(int j = 0; j < P.size(); j++){
                int v = P[j];
                if(T[v]){
                    if(color[v])
                        b1++;
                    else
                        c1++;
                }else{
                    if(color[v])
                        b2++;
                    else
                        c2++;
                }

                for(int k = 0; k < V[v].size(); k++){
                    int u = V[v][k];
                    if(color[v] == color[u])
                        cycle = true;

                    if(T[v] == T[u])
                        good = true;

                }
            }

            if(!good)
                continue;
            
            if(cycle){
                ans *= pot(2,P.size()-1);
                ans %= mod;
            }else{
                ll p = 0;
                for(int c = 0; c <= P.size(); c++){
                    
                    int _b1 = b1+c1 - c;
                    int _c1 = c;

                    int _b2 = _b1 + (b2-b1);
                    int _c2 = _c1 + (c2-c1);
                    if(_b1 < 0 || _c1 < 0 || _b2 < 0 || _c2 < 0){
                        continue;
                    }
                    p += f(b1+c1, _c1) * f(b2+c2, _c2);
                    p %= mod;
                }
                
                ans *= p;
                ans %= mod;
            }
            // printf("%d %lld*\n",i,ans);
        }
    }
    printf("%lld\n",ans);
    return 0;
}