import java.io.*; import java.util.*; public class Main { static ArrayList> graph = new ArrayList<>(); static int[] counts; public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int n = sc.nextInt(); int q = sc.nextInt(); for (int i = 0; i < n; i++) { graph.add(new ArrayList<>()); } for (int i = 0; i < n - 1; i++) { int a = sc.nextInt() - 1; int b = sc.nextInt() - 1; graph.get(a).add(b); graph.get(b).add(a); } counts = new int[n]; getCount(0, 0); long ans = 0; StringBuilder sb = new StringBuilder(); while (q-- > 0) { int idx = sc.nextInt() - 1; long x = sc.nextInt(); ans += counts[idx] * x; sb.append(ans).append("\n"); } System.out.print(sb); } static int getCount(int idx, int p) { counts[idx] = 1; for (int x : graph.get(idx)) { if (x == p) { continue; } counts[idx] += getCount(x, idx); } return counts[idx]; } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }