#include<bits/stdc++.h>
#define endl        '\n'
#define F           first
#define S           second
#define pb          push_back
#define yes         cout<<"YES\n"
#define no          cout<<"NO\n"
#define all(x)      x.begin(),x.end()
#define allr(x)     x.rbegin(),x.rend()
#define error1(x)   cerr<<#x<<" = "<<(x)<<endl
#define error2(a,b) cerr<<"("<<#a<<", "<<#b<<") = ("<<(a)<<", "<<(b)<<")\n";
#define coutall(v)  for(auto &it: v) cout << it << " "; cout << endl;
using namespace std;
using ll = long long;
using ld = long double;

void solve() {
    ll n;
    cin >> n;
    vector<ll> v(n + 1);
    for (int i = 1; i <= n; i++) {
        ll x; cin >> x;
        v[i] = x;
    }
    vector<set<ll>> g(n + 1);
    for(int i = 0; i + 1 < n; i++) {
        ll u, v; cin >> u >> v;
        g[u].insert(v);
        g[v].insert(u);
    }
    set<ll> st;
    
    while(true) {
        bool ok = 1;
        for(int i = 1; i <= n; i++) {
            if(g[i].size() == 1 && v[i] == 0) {
                g[*g[i].begin()].erase(i);
                g[i].clear();
                ok = 0;
                break;
            }
        }
        if(ok) break;
    }
    ll ans = 0;
    for(int i = 1; i <= n; i++) {
        if(g[i].size()) ++ans;
    }
    cout << ans << endl;
    return;
}

signed main() {
    ios::sync_with_stdio(false); cin.tie(0);
    int tc = 1;
    cin >> tc;
    for (int t = 1; t <= tc; t++) {
        // cout << "Case " << t << ": ";
        solve();
    }
    return 0;
}