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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int N = 5e5+10;
const int MOD = 1e9+7;

ll c[N], n, m, f[N];
vector<int> G[N], tmp;

int col[N], vx[N];
bool bip(int v, int d) {
    col[v]=d; tmp.push_back(v);
    vx[v]=true;
    for (auto u : G[v]) {
        if (!vx[u]) {
            if (!bip(u, d^1)) return false;
        } else if (col[u] == col[v]) return false;
    } return true;
}

bool v2[N];
int dfs(int v) {
    v2[v]=true;

    int res=1;
    for (auto u : G[v]) {
        if (v2[u]) continue;
        res+=dfs(u);
    } return res;
}

ll bpw(ll x, ll n) {
    if (n == 0) return 1;
    ll c=bpw(x, n/2);
    c=(c*c)%MOD;
    if (n&1) return (c*x)%MOD;
    return c;
}

ll inv(ll x) {
    return bpw(x, MOD-2);
}

ll nck(ll n, ll k) {
    if (k > n) return 0;
    return (f[n]*inv((f[k]*f[n-k])%MOD))%MOD;
}

ll calc(ll l, ll x, ll r, ll y) {
    ll res=0, mn=min(x, y);
    x-=mn, y-=mn;

    while (x <= l && y <= r) {
        (res+=(nck(l, x)*nck(r, y))%MOD)%=MOD;
        ++x, ++y;
    } return res;
}

void solve() {
    int n, m; cin>>n>>m;

    for (int i=1; i<=n; ++i) cin>>c[i];
    for (int i=1; i<=m; ++i) {
        int a, b; cin>>a>>b;
        G[a].push_back(b);
        G[b].push_back(a);
    }

    f[0]=1;
    for (ll i=1; i<=n; ++i) (f[i]=f[i-1]*i)%=MOD;

    ll ans=1;
    for (int i=1; i<=n; ++i) {
        if (v2[i]) continue;
        int sz=dfs(i);

        tmp.clear();
        if (bip(i, 0)) {
            ll l=0, r=0, x=0, y=0;
            for (auto u : tmp) {
                assert(vx[u]);
                if (col[u] == 0) {
                    ++l, x+=c[u];
                } else {
                    ++r, y+=c[u];
                }
            } assert(l+r == sz); 
            
            (ans*=calc(l, x, r, y))%=MOD;
        } else {
            (ans*=bpw(2, sz-1))%=MOD;
        }
    } cout<<ans<<"\n";
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

    int t=1; //cin>>t;
    while (t--) solve();
}