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#include <bits/stdc++.h>

using namespace std;

typedef unsigned uint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldbl;
typedef pair<int, int> pii;
typedef pair<uint, uint> puu;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<double, double> pdd;
typedef vector<int> vi;
typedef vector<uint> vu;
typedef vector<ll> vll;
typedef vector<ull> vull;
typedef vector<pii> vpii;
typedef vector<puu> vpuu;
typedef vector<pll> vpll;
typedef vector<pull> vpull;
typedef vector<string> vstr;
typedef vector<double> vdbl;
typedef vector<ldbl> vldbl;
#define pb push_back
#define ppb pop_back
#define pfr push_front
#define ppfr pop_front
#define emp emplace
#define empb emplace_back
#define be begin
#define rbe rbegin
#define all(x) (x).be(), (x).end()
#define rall(x) (x).rbe(), (x).rend()
#define fir first
#define sec second
#define mkp make_pair
#define brif(cond) if (cond) break
#define ctif(cond) if (cond) continue
#define retif(cond) if (cond) return
void canhazfast() {ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);}
template<typename T> T gcd(T a, T b) {return b ? gcd(b, a%b) : a;}
template<typename T> T extgcd(T a, T b, T &x, T &y)
{
    T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
    while (b) {
        T q = a/b; a %= b; swap(a, b);
        x0 -= q*x1; swap(x0, x1);
        y0 -= q*y1; swap(y0, y1);
    }
    x = x0; y = y0; return a;
}
int ctz(uint x) {return __builtin_ctz(x);}
int ctzll(ull x) {return __builtin_ctzll(x);}
int clz(uint x) {return __builtin_clz(x);}
int clzll(ull x) {return __builtin_clzll(x);}
int popcnt(uint x) {return __builtin_popcount(x);}
int popcntll(ull x) {return __builtin_popcountll(x);}
int bsr(uint x) {return 31^clz(x);}
int bsrll(ull x) {return 63^clzll(x);}

#define MOD 1000000007

uint add(uint a, uint b) { return a+b < MOD ? a+b : a+b-MOD; }
uint sub(uint a, uint b) { return a < b ? a+MOD-b : a-b; }
uint mul(uint a, uint b) { return (ull)a*b%MOD; }
uint sqr(uint a) { return mul(a, a); }

uint modpow(uint b, uint e)
{
    uint r = 1;
    for (; e; e >>= 1) {
        if (e&1) r = mul(r, b);
        b = sqr(b);
    }
    return r;
}

uint modpowll(uint b, ull e)
{
    uint r = 1;
    for (; e; e >>= 1) {
        if (e&1) r = mul(r, b);
        b = sqr(b);
    }
    return r;
}

uint modinv(uint n) { return modpow(n, MOD-2); }
uint moddiv(uint n, uint d) { return mul(n, modinv(d)); }

#define N 200016
#define M 400016

int c[N], q[N], par[N], vis[N];
uint fac[N];
vi adj[N];
///pii e[M];

uint binom(int n, int k)
{
    return moddiv(fac[n], mul(fac[k], fac[n-k]));
}

uint solve_cc(int s)
{
    int k = 0;
    int f[2] = {};
    //bool tree = true;
    bool odd_cycle = false;

    vis[s] = 1;
    q[k++] = s;
    for (int i = 0; i < k; ++i) {
        int u = q[i];
        for (int v : adj[u]) {
            if (vis[v]) {
                //if (v != par[u]) tree = false;
                if (vis[v] == vis[u]) odd_cycle = true;
                continue;
            }
            vis[v] = vis[u]^3;
            par[v] = u;
            q[k++] = v;
        }
        ++f[(vis[u]&1)^c[u]];
    }
    return odd_cycle ? modpow(2, k-1) : binom(k, f[0]);
}

int main()
{
    canhazfast();

    int n, m;
    uint ans = 1;

    cin >> n >> m;
    fac[0] = fac[1] = 1;
    for (int i = 2; i <= n; ++i) fac[i] = mul(fac[i-1], i);
    for (int i = 1; i <= n; ++i) cin >> c[i];
    for (int i = 0; i < m; ++i) {
        int x, y;
        cin >> x >> y;
        adj[x].pb(y);
        adj[y].pb(x);
        ///e[i] = {x, y};
    }
    for (int i = 1; i <= n; ++i) {
        ctif(vis[i]);
        ans = mul(ans, solve_cc(i));
    }
    cout << ans << '\n';

    return 0;
}