To reword the problem more precisely, we have an undirected weighted tree. Define $f(v, w)$ to be the minimum weight over all edges on the path from $v$ to $w$. We want to answer several queries for a given vertex $v$ and $k$ of the form - how many vertices $w$ exist where $f(v, w) \ge k$?

To answer this query for a given vertex, we can start by doing a BFS from $v$. We never want to traverse an edge with edge weight strictly less than $k$, so we ignore those edges. We can then count how many other vertices we have visited.

import java.io.*;
import java.util.*;
public class mootube {
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new FileReader("mootube.in"));
		PrintWriter pw = new PrintWriter(new BufferedWriter(new FileWriter("mootube.out")));
		StringTokenizer st = new StringTokenizer(br.readLine());
		int n = Integer.parseInt(st.nextToken());
		int q = Integer.parseInt(st.nextToken());
		LinkedList<Edge>[] edges = new LinkedList[n];
		for(int i = 0; i < n; i++) {
			edges[i] = new LinkedList<Edge>();
		}
		for(int a = 1; a < n; a++) {
			st = new StringTokenizer(br.readLine());
			int x = Integer.parseInt(st.nextToken())-1;
			int y = Integer.parseInt(st.nextToken())-1;
			int w = Integer.parseInt(st.nextToken());
			edges[x].add(new Edge(y, w));
			edges[y].add(new Edge(x, w));
		}
		for(int query = 0; query < q; query++) {
			st = new StringTokenizer(br.readLine());
			int threshold = Integer.parseInt(st.nextToken());
			int start = Integer.parseInt(st.nextToken())-1;
			int ret = 0;
			LinkedList<Integer> queue = new LinkedList<Integer>();
			queue.add(start);
			boolean[] seen = new boolean[n];
			seen[start] = true;
			while(!queue.isEmpty()) {
				int curr = queue.removeFirst();
				for(Edge out: edges[curr]) {
					if(!seen[out.d] && out.w >= threshold) {
						seen[out.d] = true;
						queue.add(out.d);
						ret++;
					}
				}
			}
			pw.println(ret);
		}
		pw.close();
	}
	
	static class Edge {
		public int d, w;
		public Edge(int a, int b) {
			d=a;
			w=b;
		}
	}
		
}