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

constexpr int INF = 1 << 30;

int main() {
	cin.tie(nullptr)->sync_with_stdio(false);
	int t;
	cin >> t;
	while (t--) {
		int n, k;
		cin >> n >> k;
		vector<int> a(n);
		for (int &ai : a)
			cin >> ai;
		vector<vector<int>> g(n);
		for (int i = 1; i < n; ++i) {
			int u, v;
			cin >> u >> v;
			--u, --v;
			g[u].push_back(v);
			g[v].push_back(u);
		}
		auto dfs = [&](auto self, int u, int f) -> array<int, 3> {
			array<int, 3> ret = {0, -INF, 0};
			int64_t tot = a[u];
			int diff = -INF;
			for (int v : g[u]) {
				if (v == f)
					continue;
				auto cur = self(self, v, u);
				tot += max(cur[0], cur[1]);
				diff = max(diff, -abs(cur[0] - cur[1]));
				ret[2] += cur[2];
			}
			if (tot % 2 == k % 2 and tot >= k) {
				ret[2]++;
			} else if (diff != -INF and (tot + diff) % 2 == k % 2 and (tot + diff) >= k) {
				ret[2]++;
			} else {
				ret[tot & 1] = tot;
				if (diff != -INF)
					ret[1 - (tot & 1)] = tot + diff;
			}
			return ret;
		};
		cout << dfs(dfs, 0, 0)[2] <<'\n';
	}
	return 0;
}