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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
using namespace __gnu_pbds;
using namespace std;
#define pb push_back
#define st first
#define nd second
typedef long long ll;
typedef long double ld;
const ll I = 1000LL * 1000LL * 1000LL * 1000LL * 1000LL * 1000LL;
const ll M = 1000LL * 1000LL * 1000LL + 7LL;
const int N = 1000 * 1000 + 7;
ll sil[N], osil[N];
bool vis[N], lit[N], clr[N];
int il[2];
vector<int> ed[N];

ll QP(ll a, ll n)
{
    ll ans = 1LL;
    while(n > 0LL)
    {
        if(n % 2LL == 1LL) ans = (ans * a) % M;
        a = (a * a) % M;
        n /= 2LL;
    }
    return ans;
}

void PreSil(int n)
{
    sil[0] = 1LL;
    for(int i = 1; i <= n; ++i) sil[i] = (sil[i - 1] * (ll)i) % M;
    osil[n] = QP(sil[n], M - 2LL);
    for(int i = n - 1; i >= 0; --i) osil[i] = (osil[i + 1] * (ll)(i + 1)) % M;
}

inline ll NK(int n, int k)
{
    return (((sil[n] * osil[k]) % M) * osil[n - k]) % M;
}

void DFS(int v, int c, bool &npc)
{
    vis[v] = true;
    if(!lit[v]) ++il[c];
    c ^= 1;
    clr[v] = c;
    if(lit[v]) ++il[c];
    for(int i = 0; i < (int)ed[v].size(); ++i)
    {
        if(vis[ed[v][i]] && clr[ed[v][i]] == c)
            npc = true;
        if(vis[ed[v][i]]) continue;
        DFS(ed[v][i], c, npc);
    }
}

inline ll CntNP(int n)
{
    ll ans = 0LL;
    for(int i = 0; i <= n; i += 2)
        ans += NK(n, i);
    return ans % M;
}

inline ll CntP(ll n1, ll n2)
{
    ll ans = 0;
    for(int i = 0; i <= min(n1, n2); ++i)
        ans += (NK(n1, i) * NK(n2, i)) % M;
    return ans % M;
}

void Solve()
{
    int n, m, a, b;
    ll ans = 1LL;
    cin >> n >> m;
    PreSil(n + 3);
    for(int i = 1; i <= n; ++i)
        cin >> lit[i];
    for(int i = 1; i <= m; ++i)
    {
        cin >> a >> b;
        ed[a].pb(b); ed[b].pb(a);
    }
    for(int i = 1; i <= n; ++i)
    {
        if(vis[i]) continue;
        bool npc = false;
        il[0] = 0; il[1] = 0;
        DFS(i, 0, npc);
        if(npc)
            ans *= CntNP(il[1] + il[0]);
        else
            ans *= CntP(il[1], il[0]);
        ans %= M;
    }
    cout << ans << "\n";
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    //int t; cin >> t;
    //while(t--)
        Solve();

    return 0;
}