#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN = 1e5 + 5, MAXM = 2e5 + 5, MAXLOGN = 20;
class graph{
public:
    struct Edge{
        int v, c, next;
    }t[MAXM];
    int h[MAXN], tot;
    /**
     * @brief 清空图
    */
    void init(){
        memset(h, 0, sizeof(h));
        tot = 0;
    }
    /**
     * @brief 建边
     * @param u 边的起点
     * @param v 边的终点
     * @param c 边的权值
    */
    void addEdge(int u, int v, int c){
        ++tot;
        t[tot].v = v;
        t[tot].c = c;
        t[tot].next = h[u];
        h[u] = tot;
    }
};
class point_split_tree{
private:
    const static int MAXNODE = MAXN, MAXDEP = MAXLOGN;
    //原树
    int size[MAXNODE];
    int dis[MAXNODE][MAXDEP];
    //新树
    int f[MAXNODE][2];
    int sum[MAXNODE];
    int point[MAXNODE];
    bool del[MAXNODE];
    int fa[MAXNODE];
    int depth[MAXNODE];
    int getSize(int u, int fa){
        size[u] = 1;
        for (int i = G.h[u]; i; i = G.t[i].next){
            int v = G.t[i].v, c = G.t[i].c;
            if (v == fa || del[v])
                continue;
            size[u] += getSize(v, u);
        }
        return size[u];
    }
    int getRoot(int u, int fa, int rtSize){
        for (int i = G.h[u]; i; i = G.t[i].next){
            int v = G.t[i].v;
            if (v == fa || del[v])
                continue;
            if (size[v] * 2 > rtSize)
                return getRoot(v, u, rtSize);
        }
        return u;
    }
    void getDis(int u, int fa, int d, int rtDep, int &a, int &b, int &c, int &e){
        a += d * val[u];
        b += d * val[u];
        c += val[u];
        e += val[u];
        dis[u][rtDep] = d;
        for (int i = G.h[u]; i; i = G.t[i].next){
            int v = G.t[i].v, c = G.t[i].c;
            if (v == fa || del[v])
                continue;
            getDis(v, u, d + c, rtDep, a, b, c, e);
        }
    }
    void buildTree(int u, int dep){
        depth[u] = dep;
        del[u] = true;
        getSize(u, 0);
        sum[u] += val[u];
        for (int i = G.h[u]; i; i = G.t[i].next){
            int v = G.t[i].v, c = G.t[i].c;
            if (del[v])
                continue;
            int rt = getRoot(v, u, getSize(v, u));
            Gnew.addEdge(u, rt, 0);
            fa[rt] = u;
            point[rt] = v;
            getDis(v, u, c, dep, f[u][0], f[rt][1], sum[rt], sum[u]);
            buildTree(rt, dep + 1);
        }
    }
public:
    //原树
    int val[MAXNODE];
    graph G;
    graph Gnew;
    void init(){
        buildTree(1, 1);
    }
    void change(int pos, int val){
        for (int i = pos; i; i = fa[i]){
            f[i][0] += dis[pos][depth[i]] * val;
            sum[i] += val;
            if (depth[i] != 1)
                f[i][1] += dis[pos][depth[i] - 1] * val;
        }
    }
    int query(int pos){
        int res = f[pos][0];
        for (int i = pos; fa[i]; i = fa[i]){
            res += f[fa[i]][0] + sum[fa[i]] * dis[pos][depth[i] - 1];
            res -= f[i][1] + sum[i] * dis[pos][depth[i] - 1];
        }
        return res;
    }
    int solve(int u, int ans){
        for (int i = Gnew.h[u]; i; i = Gnew.t[i].next){
            int v = Gnew.t[i].v;
            int res = query(point[v]);
            if (res < ans) 
                return solve(v, res);
        }
        return ans;
    }
};
graph G;
point_split_tree PST;
signed main(){
    int n, m;
    cin >> n >> m;
    for (int i = 1; i <= n - 1; i++){
        int u, v, c;
        cin >> u >> v >> c;
        G.addEdge(u, v, c);
        G.addEdge(v, u, c);
    }
    PST.G = G;
    PST.init();
    int ans = 0;
    while (m--){
        int pos, val;
        cin >> pos >> val;
        PST.change(pos, val);
        cout << PST.solve(1, PST.query(1)) << endl;
    }
    return 0;
}