#include <bits/stdc++.h>
using namespace std;
const int inf=1e9;

int n,ans,k;
vector<vector<int>> ver;
vector<int> a;

pair<int,int> dfs(int u,int fa=0){
	int s=0,x=(a[u]!=1?-inf:a[u]),y=(a[u]!=1?a[u]:-inf);
	vector<pair<int,int>> tmp;
	for(auto p:ver[u]){
		if(p==fa) continue;
		tmp.emplace_back(dfs(p,u));
	}
	
	s+=a[u];
	for(auto pt:tmp){
		s+=max(pt.first,pt.second);
		y+=pt.second;
	}
	y=max(y,0);
	
	for(auto pt:tmp){
		x=max(x,s-max(pt.first,pt.second)+pt.first);
	}
	if(a[u]==1) x=max(x,s);
	
	if(k%2==0&&y>=k){
		ans++;
		return make_pair(0,0);
	}
	
	if(x>=k){
		ans++;
		return make_pair(0,0);
	}
	
	return make_pair(x,y);
}

void solve(){
	cin>>n>>k;
	ans=0;
	a=vector<int>(n+1);
	for(int i=1; i<=n; i++){
		cin>>a[i];
	}
	
	ver=vector<vector<int>>(n+1);
	for(int i=1; i<n; i++){
		int x,y;
		cin>>x>>y;
		ver[x].emplace_back(y);
		ver[y].emplace_back(x);
	}
	
	dfs(1);
	
	cout<<ans<<'\n';
}

int main(){
	
	cin.tie(0),cout.tie(0)->sync_with_stdio(false);
	
	int T;
	cin>>T;
	while(T--) solve();
	
	return 0;
}