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#include "bits/stdc++.h"
using namespace std;
#define all(x) x.begin(),x.end()
template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << p.first << " " << p.second; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { string sep; for (const T &x : v) os << sep << x, sep = " "; return os; }
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#define ASSERT(...) 42
#endif
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pi;
const int oo = 1e9;
/*

*/
const long long MD = 1e9+7;
template<long long MOD=MD> struct mdint {
    int d;
    mdint () {d=0;}
    mdint (long long _d) : d(_d%MOD){
        if(d<0) d+=MOD;
    };
    friend mdint& operator+=(mdint& a, const mdint& o) {
        a.d+=o.d; if(a.d>=MOD) a.d-=MOD;
        return a;
    }
    friend mdint& operator-=(mdint& a, const mdint& o) {
        a.d-=o.d; if(a.d<0) a.d+=MOD;
        return a;
    }
    friend mdint& operator*=(mdint& a, const mdint& o) {
        return a = mdint((ll)a.d*o.d);
    }
    mdint operator*(const mdint& o) const {
        mdint res = *this;
        res*=o;
        return res;
    }
    mdint operator+(const mdint& o) const {
        mdint res = *this;
        res+=o;
        return res;
    }
    mdint operator-(const mdint& o) const {
        mdint res = *this;
        res-=o;
        return res;
    }
    mdint operator^(long long b) const {
        mdint tmp = 1;
        mdint power = *this;
        while(b) {
            if(b&1) {
                tmp = tmp*power;
            }
            power = power*power;
            b/=2;
        }
        return tmp;
    }
    friend mdint operator/=(mdint& a, const mdint& o) {
        a *= (o^(MOD-2));
        return a;
    }
    mdint operator/(const mdint& o) {
        mdint res = *this;
        res/=o;
        return res;
    }
    bool operator==(const mdint& o) { return d==o.d;}
    bool operator!=(const mdint& o) { return d!=o.d;}
    friend istream& operator>>(istream& c, mdint& a) {return c >> a.d;}
    friend ostream& operator<<(ostream& c, const mdint& a) {return c << a.d;}
};
using  mint = mdint<MD>;
const int mxF = 2e6+2;
mint fact[mxF], ifact[mxF];
mint ncr(int a, int b) {
    if(b>a or a<0 or b<0) return 0;
    return fact[a]*ifact[b]*ifact[a-b];
}
void precomp() {
    fact[0]=1;
    for(int i=1;i<mxF;++i) {
        fact[i]=fact[i-1]*i;
    }
    ifact[mxF-1] = mint(1)/fact[mxF-1];
    for(int i=mxF-2;i>=0;--i) {
        ifact[i]=ifact[i+1]*(i+1);
    }
}
int main() {
    precomp();
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n,m; cin >> n >> m;
    vector<bool> col(n),vis(n);
    vi c(n);
    for(auto& i : c) cin >> i;
    vvi adj(n);
    for(int i=0;i<m;++i) {
        int u,v; cin >> u >> v;
        --u,--v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    mint ans=1;
    for(int i=0;i<n;++i) if(!vis[i]) {
        int a[2][2] = {};
        bool bipart=1;
        auto dfs = [&](auto&& self, int at) -> void {
            vis[at]=1;
            a[c[at]][col[at]]++;
            for(int to : adj[at]) {
                if(vis[to]) {
                    if(col[to]==col[at]) bipart=0;
                } else {
                    col[to]=!col[at];
                    self(self,to);
                }
            }
        };
        dfs(dfs,i);
        if(bipart) {
            int total = a[0][0]+a[0][1]+a[1][0]+a[1][1];
            int asz= a[0][0]+a[1][0];
            int bsz = total-asz;
            mint cur=0;
            for(int exch=-total;exch<=total;++exch) {
                cur+=ncr(asz,a[0][0]+exch)*ncr(bsz,a[0][1]+exch);
            }
            ans*=cur;
        } else {
            int zs = a[0][0]+a[0][1];
            int os = a[1][0]+a[1][1];
            // everything is possible with the right parity?
            ans*=mint(2)^(zs+os-1);
        }

    }
    cout << ans << '\n';

// 2 3 6 10 35 70 126
}