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#include <bits/stdc++.h>
using namespace std;

constexpr int maxN = 2e5;
constexpr long long MOD = 1e9 + 7;

int n, m;
int c[maxN + 1];
int a, b;

vector<int> V[maxN + 1];
bool visited[maxN + 1];

bool col[maxN + 1];
int cnt0, cnt1, lit0, lit1, sz;
long long pow_2[maxN], bin1[maxN + 1], bin2[maxN + 1];

long long ans = 1;

bool DFS(int v) {
    bool biparite = true;
    
    visited[v] = true;

    if(col[v]) {
        cnt1++;
        lit1 += c[v];
    }
    else {
        cnt0++;
        lit0 += c[v];
    }

    sz++;

    for(int u : V[v]) {
        if(!visited[u]) {
            col[u] = !col[v];
            biparite &= DFS(u);
        }
        else {
            if(col[v] == col[u]) {
                biparite = false;
            }
        }
    }

    return biparite;
}

long long extGcd(long long a, long long b, long long &x, long long &y) {
    if(a == 0) {
        x = 0;
        y = 1;
        
        return b;
    }
 
    long long x1, y1;
    long long gcd = extGcd(b % a, a, x1, y1);
 
    x = y1 - (b / a) * x1;
    y = x1;
 
    return gcd;
}

long long inverse(long long v) {
    long long x, y;
    long long g = extGcd(v, MOD, x, y);

    long long res = x % MOD;
    
    if(res < 0) {
        res += MOD;
    }

    return res;
}

long long calc(long long x, long long y) {
    x %= MOD;
    
    long long inv = inverse(y);

    return (x * inv) % MOD;
}

long long sumNewt(int n1, int n2, int diff) {
    long long res = 0;

    bin1[0] = 1;
    for(int i=1; i<=n1; i++) {
        bin1[i] = calc(bin1[i - 1] * (n1 - i + 1), i);
    }

    bin2[0] = 1;
    for(int i=1; i<=n2; i++) {
        bin2[i] = calc(bin2[i - 1] * (n2 - i + 1), i);
    }

    for(int i=0; i+diff<=n1 && i<=n2; i++) {
        res += (bin1[i + diff] * bin2[i]) % MOD;
        res %= MOD;
    }

    return res;
}

long long solve(int v) {
    cnt0 = cnt1 = lit0 = lit1 = sz = 0;

    bool biparite = DFS(v);

    if(!biparite) {
        return pow_2[sz - 1];
    }

    if(lit0 < lit1) {
        swap(cnt0, cnt1);
        swap(lit0, lit1);
    }

    return sumNewt(cnt0, cnt1, lit0 - lit1);
}

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

    cin >> n >> m;

    for(int i=1; i<=n; i++) {
        cin >> c[i];
    }

    for(int i=1; i<=m; i++) {
        cin >> a >> b;

        V[a].push_back(b);
        V[b].push_back(a);
    }

    pow_2[0] = 1;
    for(int i=1; i<=n-1; i++) {
        pow_2[i] = (pow_2[i - 1] << 1) % MOD;
    }

    for(int i=1; i<=n; i++) {
        if(!visited[i]) {
            ans *= solve(i);
            ans %= MOD;
        }
    }

    cout << ans;
}