// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops",
// "omit-frame-pointer", "inline") #pragma GCC
// target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx,avx2,fma,tune=native")
// #pragma GCC option("arch=native", "no-zero-upper") // Enable AVX

/// UH Top
#include <bits/stdc++.h>
#define db(x)   cerr << #x << ':' << (x) << '\n';
#define all(v)  (v).begin(), (v).end()
#define allr(v) (v).rbegin(), (v).rend()
#define int     ll
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
// typedef __int128_t int128;
typedef pair<ll, ll> pii;
typedef pair<ld, ll> pdi;
typedef pair<ld, ld> pdd;
typedef pair<ld, pdd> pdp;
typedef pair<string, ll> psi;
typedef pair<ll, string> pls;
typedef pair<string, string> pss;
typedef pair<ll, pii> pip;
typedef pair<pii, pii> ppp;
typedef complex<ld> point;
typedef vector<point> polygon;
typedef vector<ll> vi;
typedef pair<point, int> ppi;
typedef vector<pii> vpii;
typedef vector<vi> vvi;
#define prec(n)                                                                \
	cout.precision(n);                                                         \
	cout << fixed
const ll mod = (998244353);
const ld eps = (1e-9);
const ll oo = (ll)(1e18 + 5);
#define pi   acos(-1)
#define MAXN (ll)(1e6 + 5)

vector<int> g[MAXN];
int c[MAXN], k;
pii sum[MAXN];

int dfs(int u, int p) {
	int ans = 0;
	sum[u].second = 1e7;
	sum[u].first = c[u];
	int cnt = 0;
	for (auto v : g[u]) {
		if (v == p)
			continue;
		ans += dfs(v, u);
		cnt++;
		sum[u].first += sum[v].first;
		sum[u].second = min(sum[u].second, sum[v].second);
	}

	if (c[u] == 1) {
		sum[u].second = min(sum[u].second, sum[u].first - 1);
	}
	if (!cnt) {
		if (c[u] == 0) {
			return 0;
		}
		if (c[u] == 1) {
			if (k == 1) {
				sum[u] = pii(0, 1e7);
				return 1;
			}
			return 0;
		}
		if (k == 2) {
			sum[u] = pii(0, 1e7);
			return 1;
		}
		return 0;
	}
	if (sum[u].first >= k && (sum[u].first - k) % 2 == 0) {
		sum[u] = pii(0, 1e7);
		ans++;
		return ans;
	}
	if (sum[u].first < k) {
		return ans;
	}
	// sum.f > k, imp
	if (sum[u].first - sum[u].second >= k) {
		sum[u] = pii(0, 1e7);
		ans++;
		return ans;
	}
	int d = sum[u].first - k + 1;
	sum[u].first -= d;
	sum[u].second -= d;
	return ans;
}

int32_t main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int t;
	cin >> t;
	while (t--) {
		int n;
		cin >> n >> k;
		for (int i = 0; i < n; i++)
			cin >> c[i];
		for (int i = 0; i < n - 1; i++) {
			int u, v;
			cin >> u >> v;
			u--, v--;
			g[u].push_back(v);
			g[v].push_back(u);
		}

		cout << dfs(0, -1) << "\n";

		for (int i = 0; i < n; i++) {
			g[i].clear();
			c[i] = 0;
			sum[i] = pii(0, 0);
		}
	}

	return 0;
}