#include <bits/stdc++.h>
#ifdef LOCAL
#include "./debug.cpp"
#else
#define debug(...)
#define print_line
#endif
using namespace std;
using ll = long long;

int N, Q;
vector<int> G[1 << 17];
int C[1 << 17];

void dfs(int now, int pre) {
    for (int nxt : G[now]) {
        if (nxt != pre) {
            dfs(nxt, now);
            C[now] += C[nxt];
        }
    }
    C[now]++;
}

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

    ll now = 0;
    while (Q--) {
        int p, x;
        cin >> p >> x;
        p--;
        now += 1ll * C[p] * x;
        cout << now << '\n';
    }
}