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

using ll = long long;

void dfs(vector<vector<int>> &G, vector<ll> &dp, int v) {
  ll now = 1;
  dp[v] = 1;
  for (int i = 0; i < G[v].size(); i++) {
    if (dp[G[v][i]] == -1) {
      dfs(G, dp, G[v][i]);
      now += dp[G[v][i]];
    }
  }
  dp[v] = now;
  return;
}

int main() {
  int n, q;
  cin >> n >> q;

  vector<vector<int>> G(n);
  for (int i = 0; i < n - 1; i++) {
    int a, b;
    cin >> a >> b;
    a--;
    b--;
    G[a].emplace_back(b);
    G[b].emplace_back(a);
  }

  vector<ll> dp(n, -1);
  dp[0] = n;
  dfs(G, dp, 0);

  ll ans = 0;

  while (q--) {
    int p;
    ll x;
    cin >> p >> x;
    p--;
    ans += x * dp[p];
    cout << ans << '\n';
  }
}