#include <bits/stdc++.h>
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
#endif
using namespace std;
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#define ll long long
#define forin(in ,n) for(ll i=0; i<n; i++) cin>>in[i]
#define forout(out) for(ll i=0; i<(ll)out.size(); i++) cout<<out[i]<<endl
#define rep(i, n) for (ll i = 0; i < n; ++i)
#define rep_up(i, a, n) for (ll i = a; i < n; ++i)
#define rep_down(i, a, n) for (ll i = a; i >= n; --i)
#define P pair<ll, ll>

#define all(v) v.begin(), v.end()
#define fi first
#define se second
#define vvvll vector<vector<vector<ll>>>
#define vvll vector<vector<ll>>
#define vll vector<ll>
#define pqll priority_queue<ll>
#define pqllg priority_queue<ll, vector<ll>, greater<ll>>

constexpr ll INF = (1ll << 60);
//constexpr ll mod = 1000000007;
constexpr ll mod = 998244353;

vll seen(100001);
vll cnt(100001);

void dfs(vvll &G, ll v){
    ll res=1;
    seen[v]=1;
    for(auto e:G[v]){
        if(seen[e]==1) continue;
        dfs(G,e);
        res+=cnt[e];
    }
    cnt[v]=res;
}

void solve(){
    ll n,q,sum=0,ans=0;
    cin>>n>>q;
    if(n<2||n>100000||q<1||q>100000){
        cout<<"Error"<<endl;
        return;
    }
    vvll G(n);
    rep(i,n-1){
        ll a,b;
        cin>>a>>b;
        if(a>n||a<1||b>n||b<1){
            cout<<"Error"<<endl;
            return;
        }
        a--;b--;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    dfs(G,0);
    rep(i,q){
        ll p,x;
        cin>>p>>x;
        if(p<1||p>n||x<1||x>100000000){
            cout<<"Error"<<endl;
            return;
        }
        p--;
        sum+=cnt[p]*x;
        cout<<sum<<endl;
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    // cout << fixed << setprecision(16);
    //ll T;
    //cin>>T;
    //rep(ca,T) 
    solve();
    
}