#include <bits/stdc++.h>
using namespace std;
#define SC               scanf
#define PF               printf
#define ull              unsigned long long
#define ld               long double
#define F                first
#define S                second
#define pb               push_back
#define sort_a(a)        sort(a.begin(),a.end());
#define sort_d(a)        sort(a.rbegin(),a.rend());
#define READ(f)          freopen(f, "r", stdin)
#define WRITE(f)         freopen(f, "w", stdout)
#define rev(s)           reverse(s.begin(),s.end())
#define P(ok)            cout << (ok ? "YES\n": "NO\n")
#define __Heart__              ios_base :: sync_with_stdio(false); cin.tie(NULL);
#define ll long long
typedef pair< ll , ll>                   PII;
const int MX = 1e5 + 5 ;
vector<int> Edge[MX] ;
int cnt = 0  , n , u , v , farthestNode = 0 , days = 0 , lev[MX] , A[MX];
void dfs(int id , int par){
  for(auto child : Edge[id]){
    if(child != par){
        lev[child] = lev[id] + 1 ;
        if(days < lev[child] ){
            days = lev[child] ;
           if(A[child]) farthestNode = child ;
        }
        dfs(child , id) ;
    }
  }
}
void dfs2(int id , int par){
  for(auto child : Edge[id]){
    if(child != par){
        lev[child] = lev[id] + 1 ;
        dfs2(child , id) ;
    }
  }
}
void solve()
{
    cin >> n ;
    int apple = 0 , st = 0 , en = 0;
    days = 0 , farthestNode = 0;
    for(int i = 1 ; i <= n ; i++) {cin >> A[i] , lev[i] = 0 , Edge[i].clear(); if(A[i]) apple = i ;}
    for(int i = 1 ; i < n ; i++){
        cin >> u >> v ;
        Edge[u].pb(v) ;
        Edge[v].pb(u) ;

    }
    dfs(apple , -1) ;
    for(int i = 1 ; i <= n ; i++) lev[i] = 0;
    cnt = 0 , days = 0 , st = farthestNode;
    dfs(farthestNode , -1) ;
    en = farthestNode ;
    for(int i = 1 ; i <= n ; i++) lev[i] = 0 ;
    dfs2(st , -1) ;
    map < int , int > freq ;
    for(int i = 1 ; i <= n ; i++)
    {
        if(A[i]) freq[lev[i]]++ ;
    }
    ll Ans = 0 ;
    for(int i = 1 ; i <= lev[en] ; i++){
        if(freq[i] > 1) {
            Ans += ((freq[i] - 1) * 2 );
        }
        Ans ++ ;
    }
    if(!en) Ans = 0 ;
    cout << Ans << "\n";

}
int main()
{
     __Heart__
     int t ; cin >> t ; while(t--) solve() ;
}