#include <bits/stdc++.h>
using namespace std;
#define REP(i,n) for (int i = 0; i < (n); ++i)
template<class T> inline bool chmin(T& a, T b) {if (a > b) {a = b;return true;}return false;}
template<class T> inline bool chmax(T& a, T b) {if (a < b) {a = b;return true;}return false;}
using ll = long long;
using P = pair<int,int>;
using Pl = pair<long long,long long>;
using veci = vector<int>;
using vecl = vector<long long>;
using vecveci = vector<vector<int>>;
using vecvecl = vector<vector<long long>>;
const int MOD = 1000000007;
const double pi = acos(-1);
ll gcd(ll a, ll b) {if(b == 0) return a; else return gcd(b,a%b);}
ll lcm(ll a, ll b) {return a*b/gcd(a,b);}

vecveci G(100010);
veci dp(100010,0);
veci seen(100010);

void dfs(int i) {
    seen[i] = 1;
    for(int ni : G[i]) {
        if(seen[ni]) continue;
        dfs(ni);
        dp[i] += dp[ni];
    }
    dp[i]++;
}

int main() {
    int N,Q; cin >> N >> Q;
    ll tot = 0;
    REP(i,N-1) {
        int a,b; cin >> a >> b;
        a--,b--;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    dfs(0);

    // REP(i,N) cout << dp[i] << " ";
    // cout << endl;

    REP(i,Q) {
        int p; cin >> p; p--;
        ll x; cin >> x;
        tot += x*dp[p];
        cout << tot << endl;
    }
    return 0;
}