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//
// Mateusz Pietrowcow
//
 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
 
#define MODLL 1000000007LL
#define MODULL 1000000007ULL
#define INF 1000000000
#define INFL 1000000000000000000LL
#define Tak cout << "TAK" << '\n'
#define Nie cout << "NIE" << '\n'
#define min3(x, y, z) min(x, min(y, z))
#define max3(x, y, z) max(x, max(y, z))
#define all(x) x.begin(),x.end()
 
using namespace std;
 
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int,int> ii;
typedef pair<long long, long long> pll;
typedef pair<unsigned long long, unsigned long long> pull;

const int N = 2e5 + 5;

vector<int> g[N];
bitset<N> t, visited;
ull silnia[N];
ll pref[N];
int type[N];
int n, m, k, p, np, lp, lnp;
bool cp, cnp;

inline ll mod(ll a)
{
    return ((a % MODULL) + MODLL) % MODLL;
}

inline ull mod(ull a)
{
    return a % MODULL;
}

ull fastPot(ull a, ull b)
{
    ull r = 1;

    while (b != 0)
    {
        if (b % 2 == 1)
            r = mod(r * a);
        a = mod(a * a);
        b /= 2;
    }

    return r;
}

ull newton(ull n, ull k)
{
    ull r = silnia[n], pot = fastPot(mod(silnia[k] * silnia[n - k]), MODULL - 2);
    return mod(r * pot);
}

void init()
{
    silnia[0] = 1;
    for (ull i = 1; i <= n; i++)
        silnia[i] = mod((ull)silnia[i - 1] * i);
}

int mod2(int a)
{
    return ((a % 2) + 2) % 2;
}

void read()
{
    cin >> n >> m;

    for (int i = 1; i <= n; i++)
    {
        bool c;
        cin >> c;
        t[i] = c;
    }

    for (int i = 0; i < m; i++)
    {
        int a, b;
        cin >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
}
 
void dfs(int v, int par)
{
    visited[v] = true;
    type[v] = !type[par];

    if (type[v]) 
    {
        lnp++;
        np += t[v];
    }
    else 
    {
        lp++;
        p += t[v];
    }
    
    k++;

    for (auto i : g[v])
    {
        if (visited[i])
        {
            bool r1 = type[i],
                 r2 = type[v];

            if (r1 == r2)
            {
                if (!r1) cp = true;
                else cnp = true;
            }
        }
        else
            dfs(i, v);
    }
}

void solve()
{
    init();

    ull res = 1;

    for (int i = 1; i <= n; i++)
    {
        if (visited[i]) continue;

        k = p = np = lp = lnp = cp = cnp = 0;
        type[i] = true;

        dfs(i, i);

        if (k == 1) continue;

        ull r = 0;

        if (!cp && !cnp)
        {
            int z = min(np, p);
            p = (p - z);
            np = (np - z);

            for (int i = 0; i <= min(lnp - np, lp - p); i++)
                r = mod(r + mod(newton(lnp, np + i) * newton(lp, p + i)));
        }
        else 
        {
            int z = min(np, p);
            p = (p - z) % 2;
            np = (np - z) % 2;

            pref[0] = pref[1] = 0;

            for (int i = 2; i <= lnp + 2; i += 2)
                pref[i] = mod(pref[i - 2] + newton(lnp, i - 2));
            for (int i = 3; i <= lnp + 2; i += 2)
                pref[i] = mod(pref[i - 2] + newton(lnp, i - 2));

            for (int i = 0; i <= lp; i++)
            {
                int start = (mod2(np + i - p)),
                    end = lnp - ((mod2(np + i - p)) ^ (lnp % 2));

                if (start > lp) continue;

                r += mod(newton(lp, i) * mod(pref[end + 2] - pref[start]));
                r = mod(r);
            }
        }

        res = mod(res * r);
    }

    cout << res;
}
 
int main()
{
    ios_base::sync_with_stdio(0);
    cout.tie(0);
    cin.tie(0);
 
    read();
    solve();
}