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#include <vector>
#include <utility>
#include <cstdio>

#define REP(a, n) for (int a = 0; a < (n); ++a)
#define FOR(a, b, c) for (int a = (b); a <= (c); ++a)

using namespace std;

typedef long long LL;

///////////////////////////

#define MOD 1'000'000'007

void gcdExtended(LL a, LL b, LL &x, LL &y) {
    if (a == 0) {
        x = 0, y = 1;
    }
    else {
        LL y1;
        gcdExtended(b % a, a, y, y1);
        x = y1 - (b / a) * y;
    }
}

LL inv(int A)
{
    LL x, y;
    gcdExtended(A, MOD, x, y);
    return (x % MOD + MOD) % MOD;
}

#define MAXN 200005

int byl[MAXN], pocz[MAXN], N;
vector<int> sas[MAXN];
int rozm[3], ile1[3], dwudz;

void dfs(int a, int s) {
    if (byl[a] && byl[a]!=s) dwudz = 0;
    if (byl[a]) return;
    byl[a] = s;
    rozm[s]++;
    ile1[s] += pocz[a];
    for (int x : sas[a])
        dfs(x, 3-s);
}

LL res = 1, silnia[MAXN] = {1};

LL noverk(int n, int k) {
    return silnia[n] * inv(silnia[k]) % MOD * inv(silnia[n-k]) % MOD;
}

int main() {
    int M;
    scanf("%d%d", &N, &M);
    FOR(a, 1, N) {
        scanf("%d", &pocz[a]);
        silnia[a] = silnia[a-1]*a%MOD;
    }
    REP(a, M) {
        int x, y;
        scanf("%d%d", &x, &y);
        sas[x].push_back(y);
        sas[y].push_back(x);
    }
    FOR(a, 1, N)
        if (!byl[a]) {
            dwudz = 1;
            ile1[1] = ile1[2] = rozm[1] = rozm[2] = 0;
            dfs(a, 1);
            if (dwudz) {
                LL rr = 0;
                FOR(i11, 0, rozm[1]) {
                    int i12 = i11-ile1[1]+ile1[2];
                    if (i12<0 || i12>rozm[2]) continue;
                    rr += noverk(rozm[1], i11) * noverk(rozm[2], i12) % MOD;
                }
//                printf("dwudz: %lld\n", rr);
                res = rr % MOD * res % MOD;
            } else {
                int r = rozm[1]+rozm[2]-1;
                LL w = 1;
                while (r) { w = w*2 % MOD; --r; }
//                printf("dowolny: %lld\n", w);
                res = res * w % MOD;
            }
        }
    printf("%lld\n", res%MOD);
}