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

#define ll long long
#define rep(i, n) for (int i = 0; i < (n); i++)
#define P pair<int, int>

vector<int> G[100005];
int c[100000];

void dfs(int v, int p = -1) {
  for (int nv : G[v]) {
    if (nv == p) continue; 
    dfs(nv, v);
    c[v]++;
    c[v]+=c[nv];
  }
}

int main() {
  int n, q;
  cin >> n >> q;
  rep(i,n-1) {
    int a, b;
    cin >> a >> b;
    a--, b--;
    G[a].push_back(b);
    G[b].push_back(a);
  }
  dfs(0);
  ll ans = 0;
  rep(qi,q) {
    int p;
    ll x;
    cin >> p >> x;
    p--;
    ans += x*(c[p]+1);
    cout << ans << endl;
  }




}