#include <bits/stdc++.h>
using namespace std;
int main(){
  int N, Q;
  cin >> N >> Q;
  vector<vector<int>> E(N);
  for (int i = 0; i < N - 1; i++){
    int a, b;
    cin >> a >> b;
    a--;
    b--;
    E[a].push_back(b);
    E[b].push_back(a);
  }
  vector<int> pr(N, -1);
  vector<vector<int>> ch(N);
  queue<int> q;
  q.push(0);
  vector<int> bfs;
  while (!q.empty()){
    int v = q.front();
    q.pop();
    bfs.push_back(v);
    for (int w : E[v]){
      if (w != pr[v]){
        pr[w] = v;
        ch[v].push_back(w);
        q.push(w);
      }
    }
  }
  reverse(bfs.begin(), bfs.end());
  vector<int> dp(N, 1);
  for (int v : bfs){
    for (int w : ch[v]){
      dp[v] += dp[w];
    }
  }
  long long ans = 0;
  for (int i = 0; i < Q; i++){
    int p, x;
    cin >> p >> x;
    p--;
    ans += (long long) dp[p] * x;
    cout << ans << endl;
  }
}