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

int dp[100005];
vector<int>ki[100005];

int dfs(int n,int p) {
    int res = 0;
    for(int i = 0; i < ki[n].size(); i++) {
        if(ki[n][i] == p) {
            continue;
        }
        res += dfs(ki[n][i],n);
    }
    res++;
    return dp[n] = res;
}

int main() {
    int N,Q;
    cin >> N >> Q;
    for(int i = 0; i < N-1; i++) {
        int a,b;
        cin >> a >> b;
        a--;
        b--;
        ki[a].push_back(b);
        ki[b].push_back(a);
    }
    dfs(0,-1);
    long long sum = 0;
    for(int i = 0; i < Q; i++) {
        int p,x;
        cin >> p >> x;
        p--;
        sum += (long long)(x)*dp[p];
        cout << sum << endl;
    }
}