gistfile1.txt

#include <iostream>
#include <limits>
#include <sstream>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;

#define forn(i, n) for (int i = 0; i < n; i++)
typedef vector<int> vi;
typedef pair<int, int> pi;

int n, m, a[111111], x, y, res = 0;

int main() {
	freopen("aplusb.in", "r", stdin); freopen("aplusb.out", "w", stdout);
	cin >> n >> m;
	forn(i, n) cin >> a[i];
	vector<vi> g(n, vi());
	vi used(n, 0);
	forn(i, n - 1) {
		cin >> x >> y;
		x--; y--;
		g[x].push_back(y);
		g[y].push_back(x);
	}
	queue<pi> q;
	q.push(make_pair(0, a[0]));
	while (!q.empty()) {
		pi v = q.front();
		used[v.first] = 1;
		cout << v.first << endl;
		q.pop();
		forn(i, g[v.first].size()) {
			cout << g[i].size() << " " << i << endl;
			if (g[i].size() == 1 && i != 0) {
				res++;
				continue;
			}
			int next = g[v.first][i], d = v.second;
			if (used[next]) continue;
			if (a[next] == 0) {
				d = 0;
			}
			else {
				d += 1;
			}
			if (d > m) continue;
			q.push(make_pair(next, d));
		}
	}
	cout << res;
	return 0;
}