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#include <bits/stdc++.h>
#define FOR(i, a, b) for(int i =(a); i < (b); ++i)
#define re(i, n) FOR(i, 1, n)
#define ford(i, a, b) for(int i = (a); i >= (b); --i)
#define rep(i, n) for(int i = 0;i <(n); ++i)
#define all(x) (x).begin(), (x).end()
#define sz(x) (int) (x).size()

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
typedef vector<ll> vll;
typedef vector<int> vi;
typedef vector<pll> vpll;
typedef vector<pii> vpii;

const ll inf = 1e18;
const int N = 5005;
const int mod = 1e9 + 7;
const int BASE = 3;

vll twopow;
int n, m;
vector<pii> edges;
unordered_set<ll> vis;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> m;
    twopow.resize(n+1);
    twopow[0] = 1;
    vector<bool> fstate(n);
    rep(i, n)
    {
        twopow[i+1] = twopow[i] * BASE;
    }
    rep(i, n) 
    {
        bool f;
        cin >> f;
        fstate[i] = f;
    }
    rep(i, m)
    {
        int a, b;
        cin >> a >> b;
        a--;
        b--;
        edges.push_back({a, b});
    }
    if (n <= 30)
    {
        int mask = 0;
        rep(i, n)
        {
            mask |= (fstate[i] << i);
        }
        vector<int> states;
        vector<bool> vis(1 << n);
        states.push_back(mask);
        ll cnt = 0;
        vis[mask] = true;
        while (!states.empty())
        {
            cnt++;
            int v = states.back();
            states.pop_back();
            rep(i, m)
            {
                int a = edges[i].first;
                int b = edges[i].second;
                if (!(((v >> a) ^ (v >> b)) & 1))
                {
                    int u = v ^ ((1 << a) | (1 << b));
                    if (!vis[u])
                    {
                        vis[u] = true;
                        states.push_back(u);
                    }
                }
            }
        }
        cout << cnt % mod << '\n';
    }
    else
    {
        vector<pair<vector<bool>, ll>> states;
        ll fstatehash = 0ll;
        rep(i, n) fstatehash += fstate[i] * twopow[i];
        states.push_back({fstate, fstatehash});
        ll cnt = 0;
        vis.insert(fstatehash);
        while (!states.empty())
        {
            cnt++;
            auto vp = states.back();
            states.pop_back();
            auto v = vp.first;
            ll h = vp.second;
            rep(i, m)
            {
                int a = edges[i].first;
                int b = edges[i].second;
                if (v[a] == v[b])
                {
                    ll uh;
                    if (v[a]) uh = h - twopow[a] - twopow[b];
                    else uh = h + twopow[a] + twopow[b];
                    if (vis.find(uh) == vis.end())
                    {
                        vis.insert(uh);
                        v[a] = !v[a];
                        v[b]  = !v[b];
                        states.push_back({v, uh});
                        v[a] = !v[a];
                        v[b]  = !v[b];
                    }
                }
            }
        }
        cout << cnt % mod << '\n';
    }
}