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

const int MAXN = 2e5 + 7;
const int MOD = 1e9 + 7;
const int P = 313;
int state[MAXN];
ll pot[MAXN];
vector<pair<int, int>> edges;
unordered_set<ll> was;
int n, m;
ll akt;
ll ans = 0;

void backtrack(){
    if(was.count(akt)){
        return;
    }
    was.insert(akt);
    ans++;
    /*cout << akt << '\n';
    for(int i = 0; i < n; i++){
        cout << state[i] << ' ';
    } 
    cout << '\n';*/
    
    int u, v;
    ll prevHash;
    for(int i = 0; i < m; i++){
        u = edges[i].first - 1;
        v = edges[i].second - 1;
        if(state[u] == state[v]){
            prevHash = akt;
            if(state[u] == 1){
                state[u] = 0;
                state[v] = 0;
                akt = (ll)akt - pot[u] - pot[v] + MOD;
                akt += MOD;
                akt %= MOD;
            }else{
                state[u] = 1;
                state[v] = 1;
                akt = (ll)akt + pot[u] + pot[v] + MOD;
                akt += MOD;
                akt %= MOD;
            }
            backtrack();
            akt = prevHash;
            if(state[u] == 1){
                state[u] = 0;
                state[v] = 0;
            }else{
                state[u] = 1;
                state[v] = 1;
            }
        }
    }
}

void preprocessing(){
    pot[0] = 1;
    for(int i = 1; i < MAXN; i++){
        pot[i] = (ll)pot[i - 1] * P;
        pot[i] %= MOD;
    }
}

ll getHash(string s){
    ll hash = 0;
    for(int i = 0; i < n; i++){
        hash = (ll)hash + (ll)pot[i] * s[i];
        hash %= MOD;
    }
    
    return hash;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    
    cin >> n >> m;
    string now = "";
    for(int i = 0; i < n; i++){
        cin >> state[i];
        if(state[i]){
            now += '1';
        }else{
            now += '0';
        }
    }
    
    preprocessing();
    akt = getHash(now);
    //cout << akt << '\n';
    int u, v;
    for(int i = 0; i < m; i++){
        cin >> u >> v;
        edges.push_back({u, v});
    }
    
    backtrack();
    
    cout << ans << '\n';
    
    return 0;
}