#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 2e5;
int a[N], d[N], sum;
vector <int> g[N];
bool Dfs(int v, int p){
    bool ok = (a[v] == 1);
    for(int u:g[v]){
        if(u != p){
            d[u] = d[v] + 1;
            ok |= Dfs(u, v);
        }
    }
    if(ok == true and v != p) sum += 2;
    return ok;
}
void dfs(int v, int p){
    for(int u:g[v]){
        if(u != p){
            d[u] = d[v] + 1;
            dfs(u, v);
        }
    }
}
void sol(){
    int n;
    cin >> n;
    for(int i = 0; i < n; i++) cin >> a[i], d[i] = 0, g[i].clear();
    for(int i = 1; i < n; i++) {
        int u, v;
        cin >> u >> v;
        u--, v--;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    dfs(0, 0);
    int node = 0, mx = 0;
    for(int i = 0; i < n; i++){
        if(a[i]){
            if(d[i] >= mx){
                mx = d[i];
                node = i;
            }
        }
        d[i] = 0;
    }
    sum = 0;
    bool ok =  Dfs(node, node);
    mx = 0;
    for(int i = 0; i < n; i++){
        if(a[i]) mx = max(mx, d[i]);
    }
    cout << sum - mx << endl;
}
signed main(){
    int t;
    cin >> t;
    while(t--){
        sol();
    }
    return 0;
}