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#include <bits/stdc++.h>

using namespace std;
#define PB push_back
#define LL long long
#define int LL
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#define FORD(i,a,b) for (int i = (a); i >= (b); i--)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define VI vector<int>
#define PII pair<int,int>
#define LD long double


template<class T> ostream &operator<<(ostream &os, vector<T> V){
    os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
}

template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
    return os << "(" << P.st << "," << P.nd << ")";
}


template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}


#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif


int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout << fixed << setprecision(11);
  cerr << fixed << setprecision(6);
  int n,m;
  cin >> n >> m;
  vector<bool> state(n);
  REP(i, n){
    int a;
    cin >> a;
    state[i] = a;
  }
  vector<PII> edges(m);
  REP(i, m){
    cin >> edges[i].st >> edges[i].nd;
    edges[i].st--;
    edges[i].nd--;
  }
  set<vector<bool>> done;
  vector<vector<bool>> todo = {state};
  done.insert(state);
  REP(i, SZ(todo)){
    vector<bool> current = todo[i];
    for(PII p: edges){
        if(current[p.st] == current[p.nd]){
            vector<bool> cp = current;
            cp[p.st].flip();
            cp[p.nd].flip();
            if(done.count(cp) == 0){
                done.insert(cp);
                todo.PB(cp);
            }
        }
    }
  }
  cout << SZ(done) << "\n";
}