#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
#else
  #define Debug(...) void(0)
#endif
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int n, q;
  cin >> n >> q;
  vector Graph(n, vector<int>(0));
  rep(_, n - 1) {
    int u, v;
    cin >> u >> v;
    --u, --v;
    Graph[u].push_back(v);
    Graph[v].push_back(u);
  }
  vector<int> dp(n, 0);
  function<void(int, int)> dfs = [&](int u, int p) {
    for (int v : Graph[u]) {
      if (v == p) continue;
      dfs(v, u);
      dp[u] += dp[v];
    }
    dp[u] += 1;
  };
  dfs(0, -1);
  ll ans = 0;
  while (q--) {
    int p, x;
    cin >> p >> x;
    --p;
    ans += (ll) dp[p] * x;
    cout << ans << '\n';
  }
  return 0;
}