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#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("bmi,bmi2,lzcnt,popcnt")

#include <bits/stdc++.h>

using namespace std;

#define endl '\n'
#define L long long
#define MP make_pair
#define REP(i, n) for(int i = 0; i < n; ++i)
#define REPR(i, n) for(int i = n - 1; i >= 0; --i)
#define FOR(i, a, b) for(int i = a; i < b; ++i)
#define FORR(i, a, b) for(int i = b - 1; i >= a; --i)
#define EB emplace_back
#define ST first
#define ND second
#define S size
#define RS resize

template<class T> using P = pair<T, T>;
template<class T> using V = vector<T>;

const L M = (int)1e9 + 7;

V<V<int>> g;
V<int> c, col;

bool bip;
array<int, 2> sizes, zeros, ones;

void dfs(int v) {
    for (int u : g[v]) {
        if (col[u] == -1) {
            {
                int tu = 1 - (col[v] & 1);
                sizes[tu]++;
                if (c[u] == 0) {
                    zeros[tu]++;
                } else {
                    ones[tu]++;
                }
                col[u] = col[v] + (tu == 1 ? 1 : -1);
            }
            dfs(u);
        } else if (col[u] == col[v]) {
            bip = false;
        }
    }
}

L power(L a, L b) {
    if (b == 0) {
        return 1LL;
    }

    if ((b & 1) == 0) {   
        L s = power(a, b >> 1LL);
        L res = s * s;
        return res >= M ? res % M : res;
    }
    else {
        L s = power(a, b - 1LL);
        L res = s * a;
        return res >= M ? res % M : res;
    }
}

L binom(int n, int k) {
    L res = 1;
    FOR(i, n - k + 1, n + 1) {
        res = (res * (L)i) % M;
    }
    FOR(i, 2, k + 1) {
        res = (res * power(i, M - 2)) % M;
    }
    return res;
}

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

    int n, m;
    cin >> n >> m;
    
    g.RS(n);
    c.RS(n);
    col.RS(n, -1);

    REP(i, n) {
        cin >> c[i];
    }

    REP(i, m) {
        int a, b;
        cin >> a >> b;
        a--, b--;
        g[a].EB(b), g[b].EB(a);
    }

    V<L> pow2(n);
    pow2[0] = 1;
    FOR(i, 1, n) {
        pow2[i] = (2LL * pow2[i - 1]) % M;
    }

    L res = 1;
    REP(v, n) {
        if (col[v] == -1) {
            col[v] = 2 * v;
            bip = true;
            sizes[0] = 1;
            sizes[1] = 0;
            zeros[0] = (int)(c[v] == 0);
            zeros[1] = 0;
            ones[0] = (int)(c[v] == 1);
            ones[1] = 0;
            dfs(v);
            /*cout << bip << ' ' << sizes[0] << ' ' << sizes[1] << ' '
                 << zeros[0] << ' ' << zeros[1] << ' '
                 << ones[0] << ' ' << ones[1] << '\n';
            REP(i, n) {
                cout << col[i] << ' ';
            }
            cout << '\n'*/;
            if (bip) {
                int l = sizes[0], p = sizes[1];
                int a = ones[0], b = ones[1];
                int u = min(l - a, p - b);
                int d = min(a, b);
                L bl = binom(l, a - d);
                L bp = binom(p, b - d);
                L r = (bl * bp) % M;
                //cout << bl << ' ' << bp << '\n';
                FOR(i, 1, u + d + 1) {
                    bl = (((bl * (L)(l - a + d - i + 1)) % M) * power(a - d + i, M - 2)) % M;
                    bp = (((bp * (L)(p - b + d - i + 1)) % M) * power(b - d + i, M - 2)) % M;
                    //cout << bl << ' ' << bp << '\n';
                    r = (r + bl * bp) % M;
                }
                res = (res * r) % M;
            } else {
                res = (res * pow2[sizes[0] + sizes[1] - 1]) % M;
            }
        }
    }
    cout << res << '\n';
}