#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<bitset>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<deque>
#include<list>
#include<iomanip>
#include<cmath>
#include<cstring>
#include<functional>
#include<cstdio>
#include<cstdlib>
#include<numeric>
#include<ctime>
//#include<atcoder/all>
using namespace std;
//using namespace atcoder;

#define repr(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rep(i, n) repr(i, 0, n)
#define INF 2e9
//#define MOD 1000000007
#define MOD 998244353
#define LINF (long long)4e18
#define jck 3.141592
#define PI acos(-1.0)

const double EPS = 1e-10;

using ll = long long;
using Pi = pair<int,int>;
using Pl = pair<ll,ll>;
//using mint = modint1000000007;

int dh[] = {-1,0,1,0};
int dw[] = {0,1,0,-1};

int sz[100010];
vector<vector<int>> G;
int n,q;

void dfs(int u, int p = -1){
    sz[u] = 1;
    for(auto v : G[u]){
        if(v == p) continue;
        dfs(v,u);
        sz[u] += sz[v];
    }
}

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

    dfs(0);
    ll ans = 0;
    while(q--){
        int p,x; cin >> p >> x;
        p--;
        ans += 1LL*sz[p]*x;
        cout << ans << endl;
    }
}