#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using namespace std;
using ll=long long;
using ld=long double;
ld pie=3.141592653589793;
ll mod=998244353;
ll inf=1009999999999999990;
void dfs(ll now,vector<vector<ll>>&g,vector<ll>&dp,vector<ll>&memo){
    memo[now]=1;
    dp[now]=1;
    for (ll i = 0; i < g[now].size(); i++)
    {
        if (memo[g[now][i]]==0)
        {
            dfs(g[now][i],g,dp,memo);
            dp[now]+=dp[g[now][i]];
        }
    }
}
int main(){
    ll n,q;
    cin >>n >> q;
    vector<vector<ll>>g(n);
    for (ll i = 0; i < n-1; i++)
    {
        ll a,b;
        cin >> a >> b;
        a--,b--;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    vector<ll>dp(n,0);
    vector<ll>memo(n,0);
    dfs(0,g,dp,memo);
    ll ans=0;
    vector<ll>a;
    for (ll i = 0; i < q; i++)
    {
        ll p,x;
        cin >> p >> x;
        p--;
        ans+=x*dp[p];
        a.push_back(ans);
    }
    for (ll i = 0; i < a.size(); i++)
    {
        cout << a[i] << endl;
    }
    
}