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#include <bits/stdc++.h>
using namespace std;
 
#define fwd(i, a, n) for (int i = (a); i < (n); i ++)
#define rep(i, n) fwd(i, 0, n)
#define all(X) begin(X), end(X)
#define sz(X) ((int)X.size())
#define st first
#define nd second
#define pii pair<int, int>
#define vi vector<int>
#define ll long long
 
#ifdef LOC
auto &operator<<(auto &out, pair<auto, auto> a) {
	return out << "(" << a.st << ", " << a.nd << ")";
}
 
auto &operator<<(auto &out, auto a) {
	out << "{";
	for (auto b : a)
		out << b << ", ";
	return out << "}";
}
 
void dump(auto... x) { ((cerr << x << ", "), ...) << '\n'; }
#define debug(x...) cerr << __LINE__ << ": [" #x "]: ", dump(x)
#else
#define debug(...) 0
#endif

const ll MOD = 1e9 + 7;
 
void DFS(int v, vector<vector<int>>& g, vector<int>& myColor, vector<int>& color, ll& cntA, ll& cntB, ll& diff, bool& twoColor){
    if(myColor[v] == 1){
        cntA++;
    }else{
        cntB++;
    }
    if(color[v]){
        if(myColor[v] == 1){
            diff++;
        }else{
            diff--;
        }
    }
    for(auto u : g[v]){
        if(myColor[u] == 0){
            myColor[u] = -myColor[v];
            DFS(u, g, myColor, color, cntA, cntB, diff, twoColor);
        }else if(myColor[u] == myColor[v]){
            twoColor = false;
        }
    }
}

long long power(long long a, long long b){
    long long res = 1;
    while(b){
        while(!(b&1)){
            a = (a * a) % MOD;
            b>>=1;
        }
        res = (res * a) % MOD;
        b--;
    }
    return res;
}

vector<ll> inv;

ll magic(ll a, ll b, ll d){
    vector<ll> binomA(a+1);
    vector<ll> binomB(b+1);
    binomA[0] = 1;
    binomB[0] = 1;
    for(ll i=  1; i <= a; i++){
        binomA[i] = (a-i + 1)*inv[i] % MOD;
        binomA[i] = (binomA[i] * binomA[i-1]) % MOD;
    }
    for(ll i=  1; i <= b; i++){
        binomB[i] = (b-i + 1)*inv[i] % MOD;
        binomB[i] = (binomB[i] * binomB[i-1]) % MOD;
    }
    ll ans = 0;
    for(ll k = max(0ll, -d); k <= min(b, a- d); k++){
        ans += binomA[k+d] * binomB[k];
        ans %= MOD;
    }
    return ans;
}

int32_t main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
    int n, m; cin>>n>>m;
    inv.resize(n+1);
    vector<ll> fact(n+1);
    fact[0] = 1;
    for(ll i = 1; i <= n; i++)fact[i] = (fact[i-1] * i) % MOD;
    ll x = power(fact[n], MOD - 2);
    for(ll i = n; i >= 1; i--){
        inv[i] = (x * fact[i-1]) % MOD;
        x = (x * i) % MOD;
    }
    debug(inv);
    vector<int> color(n+1);
    rep(i, n)cin>>color[i+1];
    vector<vector<int>> g(n+1);
    rep(i, m){
        int a, b; cin>>a>>b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    ll res = 1;
    vector<int> myColor(n+1, 0);
    for(int v = 1; v <= n; v++){
        if(myColor[v] == 0){
            myColor[v] = 1;
            ll cntA = 0;
            ll cntB = 0;
            ll diff = 0;
            bool twoColor = true;
            DFS(v, g, myColor, color, cntA, cntB, diff, twoColor);
            debug(twoColor, cntA, cntB, diff);
            if(twoColor){
                res = (res * magic(cntA, cntB, diff)) % MOD;
            }else{
                res = (res * power(2, cntA + cntB - 1)) % MOD;
            }
        }
    }
    cout<<res<<"\n";
	return 0;
}