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#include <bits/stdc++.h>
using namespace std;
const int MXN=5e5+1;
int a[MXN], b[MXN], ans, n, m;
//~ bool odw[1<<29];
unordered_set<long long>odw;
void solve(long long w)
{
	odw.insert(w);
	ans++;
	for (int i=0; i<m; i++)
	{
		long long x=(1ll<<a[i]), y=(1ll<<b[i]);
		if (!(w&x)==!(w&y) && odw.find(w^x^y)==odw.end())
		{
			solve(w^x^y);
		}
	}
}
int main()
{
	cin>>n>>m;
	long long start=0;
	for (int i=0; i<n; i++)
	{
		int c; cin>>c;
		start+=c*(1ll<<i);
	}
	for (int i=0; i<m; i++)
	{
		cin>>a[i]>>b[i];
		a[i]--; b[i]--;
	}
	solve(start);
	cout<<ans<<"\n";
}