#include<bits/stdc++.h>
//#include<atcoder/all>
//#include <boost/multiprecision/cpp_int.hpp>
using namespace std;
//using namespace atcoder;
//using namespace boost::multiprecision;
#define fs first
#define sc second
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define ALL(A) A.begin(),A.end()
#define RALL(A) A.rbegin(),A.rend()
typedef long long ll;
typedef pair<ll,ll> P;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<typename T> T gcd(T a,T b){return b?gcd(b,a%b):a;}
const ll mod=1e9 + 7;
const ll LINF=1ll<<60;
const int INF=1<<30;
int dx[]={0,1,0,-1,0,1,-1,1,-1};
int dy[]={0,0,1,0,-1,1,-1,-1,1};


vector<int> G[1<<17];
vector<int> c(1<<17, 0);
int dfs(int u,int v){
    int ret = 1;
    for(auto g:G[u]){
        if(g == v) continue;
        ret += dfs(g, u);
    }
    return c[u] = ret;
}



int main(){
    int n,q;cin >>n  >> q;
    for (int i = 0; i < n-1; i++) {
        int a,b;cin >> a >> b;
        a--,b--;
        G[a].pb(b);
        G[b].pb(a);
    }
    dfs(0, 0);
    ll ans = 0;
    for (int i = 0; i < q; i++) {
        ll p,x;cin >> p >> x;
        p--;
        ans += c[p] * x;
        cout << ans << endl;
    }
    return 0;
}