#include <bits/stdc++.h>
using namespace std;
#define int long long

#define dbg(x...) \
do { \
std::cout << #x << " -> "; \
err(x); \
} while (0)

void err() {
	std::cout << std::endl;
}

template<class T, class... Ts>
void err(T arg, Ts &... args) {
	std::cout << fixed << setprecision(10) << arg << ' ';
	err(args...);
}

const int maxn = 1e6 + 5;
vector<int>t[maxn];
int c[maxn],cnt0[maxn],cnt1[maxn],cnt2[maxn],dp[maxn];
int n,k;

void dfs(int u,int f) {
	for (auto i : t[u]) {
		if (i == f) continue;
		dfs(i,u);
		cnt0[u] += cnt0[i];
		cnt1[u] += cnt1[i];
		cnt2[u] += cnt2[i];
		dp[u] += dp[i];
	}
	if (k < c[u]) {
		cnt0[u] = cnt1[u] = cnt2[u] = 0;
		return ;
	}
	if ((k - c[u]) % 2 == 0) {
		if (cnt2[u] * 2 + cnt1[u] >= (k - c[u])) {
			dp[u]++;
			cnt0[u] = cnt1[u] = cnt2[u] = 0;
		}
		else {
			if (c[u] == 0) cnt0[u]++;
			else if (c[u] == 1) cnt1[u]++;
			else cnt2[u]++;
		}
	}
	else {
		if (cnt2[u] * 2 > (k - c[u])) {
			if (cnt1[u]) {
				dp[u]++;
				cnt0[u] = cnt1[u] = cnt2[u] = 0;
			}
			else {
				if (c[u] == 0) cnt0[u]++;
				else if (c[u] == 1) cnt1[u]++;
				else cnt2[u]++;
			}
		}
		else {
			if (cnt1[u] >= (k - c[u]) - cnt2[u] * 2) {
				dp[u]++;
				cnt0[u] = cnt1[u] = cnt2[u] = 0;
			}
			else {
				if (c[u] == 0) cnt0[u]++;
				else if (c[u] == 1) cnt1[u]++;
				else cnt2[u]++;
			}
		}
	}
}

void GENSHEN_START() {
	cin >> n >> k;
	for (int i = 1;i <= n;i++) cin >> c[i];
	for (int i = 1;i <= n;i++) {
		t[i].clear();
		cnt0[i] = cnt1[i] = cnt2[i] = dp[i] = 0;
	}
	for (int i = 1;i < n;i++) {
		int u,v;cin >> u >> v;
		t[u].push_back(v);
		t[v].push_back(u);
	}
	dfs(1,0);
	cout << dp[1] << '\n';
}

signed main()
{
	ios::sync_with_stdio(false);cin.tie(nullptr);
	int T = 1;
	cin >> T;
	while (T--) GENSHEN_START();
	return 0;
}