#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef tree<pair<long long, long long>, null_type, less<pair<long long, long long>>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
// find_by_order(x) returns the xth element(0 - indexed btw)
// order_of_key(x) returns index of lower_bound of x(0 - indexed btw)
#define int long long
const int mxn = 200005;
vector<vector<int>>adj(mxn);
vector<int>sz(mxn);
vector<bool>vis(mxn);
vector<int>a(mxn);
vector<pair<int,int>>vals;
int ans = 0;
void dfs(int u, int p){
	sz[u] = 1;
	for(int nxt: adj[u]){
		if(nxt==p||vis[nxt])continue;
		dfs(nxt,u);
		sz[u]+=sz[nxt];
	}
}
int cent = 0;
int n;
void getcentroid(int u, int p){
	bool f = true;
	for(int nxt: adj[u]){
		if(nxt==p||vis[nxt])continue;
		getcentroid(nxt,u);
		if(sz[nxt]>n/2)f = false;
	}
	if(n-sz[u]>n/2)f = false;
	if(f)cent = u;
}
void dfs1(int u, int p, int sum, int d){
	for(int nxt: adj[u]){
		if(vis[nxt] || nxt == p)continue;
		dfs1(nxt,u,sum+a[nxt],max(d,a[nxt]));
	}
	if(sum-d > d)ans++;
	vals.push_back({d,sum});
}
void centroid(int x){
	dfs(x,0);
	n = sz[x];
	getcentroid(x,0);
	vis[cent] = true;
	
	{
		dfs1(cent,0,a[cent],a[cent]);
		sort(vals.begin(),vals.end());
		ordered_set t;
		for(int i = 0; i<vals.size(); i++){
			int sum = vals[i].second;
			int d = vals[i].first;
			int lookup = sum-d;

			// want some x > d - lookup
			int cnt = (int)t.size() - t.order_of_key(make_pair(d-lookup+1,0LL));
			ans+=cnt;
			t.insert({sum-a[cent],i});
		}
		vals.clear();
	}
	for(int nxt: adj[cent]){
		if(vis[nxt])continue;
		dfs1(nxt,cent,a[cent],a[cent]);
		sort(vals.begin(),vals.end());
		ordered_set t;
		for(int i = 0; i<vals.size(); i++){
			int sum = vals[i].second;
			int d = vals[i].first;
			int lookup = sum-d;

			// want some x > d - lookup
			int cnt = (int)t.size() - t.order_of_key(make_pair(d-lookup+1,0LL));
			ans-=cnt;
			t.insert({sum-a[cent],i});
		}
		vals.clear();
	}
	for(int nxt: adj[cent]){
		if(vis[nxt])continue;
		centroid(nxt);
	}
}
void reset(int n){
	for(int i = 1; i<=n; i++){
		adj[i].clear();
		vis[i] = 0;
		a[i] = 0;
		sz[i] = 0;
	}
	ans = 0;
}
signed main(){
	cin.tie(nullptr)->sync_with_stdio(false);
	int t;
	cin >> t;
	while(t--){
		cin >> n;
		int nodes = n;
		for(int i = 1; i<=n; i++){
			cin >> a[i];
		}
		for(int i = 1; i<n; i++){
			int x,y;
			cin >> x >> y;
			adj[x].push_back(y);
			adj[y].push_back(x);
		}
		centroid(1);
		cout << ans << "\n";
		reset(nodes);
	}
	return 0;
}