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#include <bits/stdc++.h>
using namespace std;
const int maxn = 1000, p = 1e9+321;
int n, m, res;
long long pot[maxn];
pair <int, int> con[maxn];
bool zap[maxn];
map <long long, bool> vis;
long long idx()
{
    long long w = 0;
    for (int i = 0; i < n; ++i)
    {
        w += zap[i] * pot[i];
    }
    return w;
}
void back_track()
{
    if (vis[idx()]) return;
    ++res;
    vis[idx()] = true;
    for (int j = 0; j < m; ++j)
    {
        pair <int, int> i = con[j];
        if (zap[i.first] == zap[i.second])
        {
            zap[i.second] = zap[i.first] = !zap[i.first];
            back_track();
            zap[i.second] = zap[i.first] = !zap[i.first];
        }
    }
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    pot[0] = 1;
    for (int i = 1; i < maxn; ++i)
    {
        pot[i] = (pot[i-1] * 2)%p;
    }
    cin >> n >> m;
    for (int i = 1; i <= n; ++i) cin >> zap[i];
    for (int i = 0; i < m; ++i)
    {
        cin >> con[i].first >> con[i].second;
    }
    back_track();
    cout << res;
}