#include <set>
#include <map>
#include <queue>
#include <ctime>
#include <cstdio>
#include <vector>
#include <cassert>
#include <cstring>
#include <algorithm>
#define fi first
#define se second
#define ep emplace
#define MISAKA main
#define ll long long
#define eb emplace_back
#define pii pair<int,int>
#define rg(x) x.begin(),x.end()
#define pc(x) __builtin_popcount(x)
#define mems(a,x) memset(a,x,sizeof(a))
#define rep(i,a,b) for(int i=(a);i<=(b);++i)
#define _rep(i,a,b) for(int i=(a);i>=(b);--i)
#define debug(...) fprintf(stderr,__VA_ARGS__)
#define FIO(FILE) freopen(FILE".in","r",stdin),freopen(FILE".out","w",stdout)
using namespace std;
bool __st;
inline int read(){
    char c=getchar();int f=1,x=0;
    for(;c<48||c>57;c=getchar())if(c=='-') f=-1;
    for(;47<c&&c<58;c=getchar()) x=(x<<3)+(x<<1)+(c^48);
    return x*f;
}
const int N=1e5+10,mod=998244353;
int n,q,rt,fa[N],F[N],vis[N],son[N],sz[N],top[N],dfn[N],tim;ll d[N],a[N],s1,s2;
vector<pii> g[N],G[N];
void dfs1(int u,int f){
    fa[u]=f,sz[u]=1;
    for(auto [v,w]:g[u])if(v!=f){
        d[v]=d[u]+w,dfs1(v,u),sz[u]+=sz[v];
        if(sz[v]>sz[son[u]]) son[u]=v;
    }
}
void dfs2(int u,int tp){
    dfn[u]=++tim,top[u]=tp;if(son[u]) dfs2(son[u],tp);
    for(auto [v,w]:g[u])if(v!=fa[u]&&v!=son[u]) dfs2(v,v);
}
#define go(u) for(auto [v,w]:g[u])if(v!=f&&!vis[v]) 
void getsz(int u,int f){sz[u]=1;go(u)getsz(v,u),sz[u]+=sz[v];}
void find(int u,int f,int n){
    int mx=n-sz[u];
    go(u) find(v,u,n),mx=max(mx,sz[v]);
    if(mx<=n/2) rt=u;
}
int bd(int u){
    getsz(u,0);find(u,0,sz[u]);int f=-1;
    vis[u=rt]=1;go(u) G[u].eb(v,bd(v));return u;
}
struct bit{
    ll c[N];bit(){mems(c,0);}
    void upd(int x,ll k){for(;x<=n;x+=x&-x)c[x]+=k;}
    ll qry(int x){ll r=0;for(;x;x^=x&-x)r+=c[x];return r;}
    ll qry(int l,int r){return l<=r?qry(r)-qry(l-1):0;}    
}t1,t2;
void upd(int u,ll k){
    t1.upd(dfn[u],k);s1+=k,s2+=k*d[u];
    for(;u;u=fa[top[u]]) t2.upd(dfn[u],k*d[u]),a[u]+=k*d[u];
}
ll qry(int u){
    ll s=d[u]*t1.qry(dfn[u],dfn[u]+sz[u]-1);int _=u;
    for(;u;u=fa[top[u]]){
        int x=top[u],y=fa[x],z=son[y];
        s+=t2.qry(dfn[x],dfn[u]-1);
        if(!y) break;
        s+=a[y]+d[y]*(-t1.qry(dfn[x],dfn[x]+sz[x]-1)+t1.qry(dfn[z],dfn[z]+sz[z]-1));
    }
    return s1*d[_]+s2-2ll*s;
}
ll solve(int u,ll x){
    if(G[u].empty()) return x;
    int id=-1;ll p=x;
    for(auto [v,x]:G[u]){
        ll t=qry(v);
        if(t<p) id=x,p=t;
    }
    return id==-1?x:solve(id,p);
}
void misaka(){
    n=read(),q=read();
    rep(i,2,n){
        int u=read(),v=read(),w=read();
        g[u].eb(v,w);g[v].eb(u,w);
    }
    rt=bd(1);dfs1(1,0);dfs2(1,1);
    while(q--){
        int u=read(),k=read();
        upd(u,k);
        printf("%lld\n",solve(rt,qry(rt)));
    }
}
bool __ed;
signed MISAKA(){
    #ifdef LOCAL_MSK
    atexit([](){
    debug("\n%.3lfs  ",(double)clock()/CLOCKS_PER_SEC);
    debug("%.3lfMB\n",abs(&__st-&__ed)/1024./1024);});
    #endif
    
    int T=1;
    while(T--) misaka();
    return 0;
}