#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0; i<(n); i++)
#define INF ((1LL<<62)-(1LL<<31))
#define all(a)  (a).begin(),(a).end()
#define rall(a)  (a).rbegin(),(a).rend()
typedef long long ll;
typedef pair<ll,ll> pl;
typedef tuple<ll,ll,ll> tupl;

int main()
{
    int n,q;
    cin >> n >> q;
    vector<vector<int>> G(n,vector<int> ());
    rep(i,n-1) {
        int a,b;
        cin >> a >> b;
        a--; b--;
        G[a].push_back(b);
    }
    ll sum=0;
    rep(i,q) {
        ll p,x;
        cin >> p >> x;
        p--;
        queue<int> q;
        q.push(p);
        while(!q.empty()) {
            int v=q.front();
            q.pop();
            sum+=x;
            for(auto nv:G[v]) q.push(nv);
        } 
        cout << sum << endl;
    }
    return 0;
}