#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define ALL(obj) (obj).begin(), (obj).end()
#define rALL(obj) (obj).rbegin(), (obj).rend()
using ll = long long;
template<class T> inline bool chmin(T& a, T b) { if ( a > b ) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if ( a < b ) { a = b; return true; } return false; }

const int INF = 1 << 30;

void dfs(int v, vector<bool> &seen,vector<vector<int>>& G) {
    if(seen[v]) return;
    seen[v] = true;
    for(int& nv: G[v]) dfs(nv, seen, G);
}


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

    ll ans = 0;
    vector<bool> seen;
    vector<ll> s(N);
    for (int i = 0; i < Q; i++) {
        ll p, x, cnt;
        cin >> p >> x;
        p--;
        if(s[p] == 0)  {
            seen.assign(N,false);
            dfs(p,seen,T);
            s[p] = count(ALL(seen), true);
        }
        ans += s[p] * x;
        cout << ans << endl;
    }
    
    return 0;
}