#include <iostream>
#include <vector>
#include <utility>
#include <atcoder/maxflow>
using namespace std;
using i32 = int32_t;
using i64 = int64_t;
#define rep(i,n) for(int i=0; i<(n); i++)


int N, Q;
vector<vector<int>> E;
vector<int> Z;
vector<i64> A;

int main(){
  cin >> N >> Q;
  E.resize(N);
  rep(i,N-1){
    int u,v; cin >> u >> v; u--; v--;
    E[u].push_back(v);
    E[v].push_back(u);
  }
  Z.assign(N,1);
  auto dfs = [&](int p,int pre,auto dfs)->void{
    for(int e : E[p]) if(pre != e){
      dfs(e,p,dfs);
      Z[p] += Z[e];
    }
  };
  dfs(0,-1,dfs);

  i64 ans = 0;
  rep(i,Q){
    int p; i64 x; cin >> p >> x; p--;
    ans += x * Z[p];
    cout << ans << "\n";
  }
  return 0;
}




struct ios_do_not_sync{
  ios_do_not_sync(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
  }
} ios_do_not_sync_instance;