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#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<ll,int> pli;
typedef pair<int,ll> pil;
typedef pair<int,int> pii;
const ll INFLL=1e18+7;
const int INF=1e9+7;
#define pb push_back
const int MAXN = 4e5+7;
bool arr[MAXN];
unordered_map<ll, bool> visited;
int a[MAXN], b[MAXN];
int n,m;
void btrack(ll mask){
    for(int i=1;i<=m;++i){
        int x = a[i], y = b[i];
        if(((mask & (1LL<<x)) > 0) == ((mask & (1LL<<y)) > 0)){
            ll _mask = mask ^ (1LL<<x) ^ (1LL<<y);
            if(!visited.count(_mask)){
                visited[_mask] = 1;
                btrack(_mask);
            }
        }
    }
}
int main()
{
	ios_base::sync_with_stdio(0);
	cin>>n>>m;
    for(int i=1;i<=n;++i) cin>>arr[i];
    for(int i=1;i<=m;++i) cin>>a[i]>>b[i];
    for(int i=1;i<=m;++i){
        --a[i]; --b[i];
    }
    ll mask = 0;
    for(int i=0;i<n;++i) if(arr[i+1]) mask |= (1LL<<i);
    visited[mask] = 1;
    btrack(mask);
    cout<<visited.size()<<"\n";
}