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#pragma GCC optimize("Ofast")
//#pragma GCC target ("avx2")
//#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include<bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//using namespace __gnu_pbds;
using namespace std;
//typedef tree<pair<int,int>,null_type,less<pair<int,int>>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
#define ll long long
#define ull unsigned long long int
#define pb push_back
#define mp make_pair
#define vi vector<int>
#define pii pair<int,int>
#define pss pair<short,short>
#define pld pair<long double,long double >
#define ld long double
#define piii  pair<pii,int>
#define vii vector<pair<int,int> >
#define st first
#define nd second
#define pll pair<ll,ll>
#define speed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define M_PI 3.14159265358979323846
#define int long long
const int mod=1000000007;
//const int mod=1009;
//const int mod=998244353;
const int inf=1000000009;
const long long INF=1000000000000000009;
const long long big=1000000000000000;
const long double eps=0.000000000000000000001;
const int rozmiar=4e5+5;
int F[rozmiar],OF[rozmiar],dwa[rozmiar];
int Pow(int a,int b){
    int wynik=1;
    while(b){
        if(b&1)
            wynik=(wynik*a)%mod;
        a=(a*a)%mod;
        b/=2;
    }
    return wynik;
}
int symbol(int a,int b){
    if(a<b)
        return 0;
    return (((F[a]*OF[b])%mod)*OF[a-b])%mod;
}
vi P[rozmiar];
int T[rozmiar],L[rozmiar];
int R[2][2];
bool O[rozmiar];
bool cycle=0;
int ile=0;
void dfs(int n,int p){
    //cout<<"elo "<<n<<endl;
    L[n]=L[p]+1;
    ile++;
    R[L[n]%2][T[n]]++;
    O[n]=1;
    for(auto v:P[n]){
        if(!O[v])
            dfs(v,n);
        else{
            int roznica=abs(L[v]-L[n]);
            if(roznica%2==0){
                cycle=1;
            }
        }
    }
}
void solve()
{
    int n,m;
    cin>>n>>m;
    F[0]=1;
    OF[0]=1;
    dwa[0]=1;
    for(int i=1;i<=n;i++){
        cin>>T[i];
        F[i]=(F[i-1]*i)%mod;
        OF[i]=Pow(F[i],mod-2);
        dwa[i]=(dwa[i-1]*2)%mod;
    }
    for(int i=1;i<=m;i++){
        int a,b;
        cin>>a>>b;
        P[a].pb(b);
        P[b].pb(a);
    }
    int wynik=1;
    for(int i=1;i<=n;i++){
        if(!O[i]){
            //cout<<"siema "<<i<<endl;
            dfs(i,0);
            int aktual=0;
            if(cycle){
                aktual=dwa[ile-1];
            }
            else{
                if(R[0][0]>R[1][0]){
                    swap(R[0][0],R[1][0]);
                    swap(R[0][1],R[1][1]);
                }
                int cur=min(R[0][0],R[1][0])+min(R[0][1],R[1][1]);
                while(R[1][0]>R[0][0]&&R[1][1]>R[0][1]){
                    R[0][0]++;
                    R[0][1]++;
                    cur++;
                }
                aktual=symbol(ile,cur);
            }
            R[0][0]=0;
            R[0][1]=0;
            R[1][0]=0;
            R[1][1]=0;
            cycle=0;
            ile=0;
            wynik=(wynik*aktual)%mod;
        }
    }
    cout<<wynik;
}
    
int32_t main(){
    speed
    int t = 1;
    //cin >> t;
    while(t--){
        solve();
    }
    return 0;
}