#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)

using std::cin;
using std::cout;
using std::vector;
using ll = long long;

const int MX = 100005;
vector<int> to[MX];
vector<int> d;
void dfs(int v, int p = -1) {
	d[v] = 1;
	for (int u : to[v]) {
		if (u == p) continue;
		dfs(u, v);
		d[v] += d[u];
	}
}

int main() {
	int n, q;
	cin >> n >> q;
	
	rep(i, n - 1) {
		int a, b;
		cin >> a >> b;
		--a; --b;
		to[a].push_back(b);
		to[b].push_back(a);
	}
	
	d.resize(n);
	dfs(0);

	ll ans = 0;
	rep(qi, q) {
		int p;
		ll x;
		cin >> p >> x;
		--p;
		ans += d[p] * x;
		cout << ans << '\n';
	}
	
	return 0;
}