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#include <iostream>  
#include <stdio.h>  
#include <string.h>   
#include <stack>  
#include <queue>   
#include <map>  
#include <set>  
#include <vector>  
#include <math.h>  
#include <bitset>  
#include <algorithm>  

using namespace std;

#define X first
#define Y second
#define eps  1e-2
#define gcd __gcd
#define pb push_back
#define PI acos(-1.0)
#define lowbit(x) (x)&(-x)
#define bug printf("!!!!!\n");
#define mem(x,y) memset(x,y,sizeof(x))

typedef long long LL;
typedef long double LD;
typedef pair<int,int> pii;
typedef unsigned long long uLL;

const int N = 1e5+2;
const int INF  = 1<<30;
const int mod  = 1e9+7;

#define int long long 

int n,k;
std::vector<pair<int,int> > g[N];
int dp[N][2];
bool cmp(pair<int,int> a,pair<int,int> b){
    if(a.first==b.first) return a.second<b.second;
    return a.first>b.first;
}
vector< pair<int,int> > tk[N];
void dfs(int x,int fa){
    for(int i=0;i<g[x].size();i++){
        int to=g[x][i].first;
        if(to==fa) continue;
        dfs(to,x);
        tk[x].push_back({dp[to][0]+g[x][i].second,to});
    }
    sort(tk[x].begin(),tk[x].end(),cmp);
    int sum=0;
    for(int i=0;i<tk[x].size();i++){
        sum+=tk[x][i].first;
        if(i>=k-1) break;
    }
    for(int i=0;i<tk[x].size();i++){
        dp[x][0]+=tk[x][i].first;
        if(i>=k-2) break;
    }

    for(int i=0;i<tk[x].size();i++){
        if(i>k-1) break;
        int to=tk[x][i].second;
        dp[x][1]=max(dp[x][1],sum-dp[to][0]+dp[to][1]);
    }
}

void solve(){
    scanf("%lld%lld",&n,&k);
    for(int i=1;i<n;i++){
        int v,u,val;
        scanf("%lld%lld%lld",&v,&u,&val);
        ++v,++u;
        g[v].push_back({u,val});
        g[u].push_back({v,val});
    }
    dfs(1,-1);
    cout<<dp[1][1]<<endl;
    return;
}

int32_t main()
{
//    freopen("in.txt","r",stdin);
//    freopen("out.txt","w",stdout);
//    ios::sync_with_stdio(false);
    int t = 1;
    //scanf("%d",&t);
    while(t--){
    //    printf("Case %d: ",cas++);
        solve();
    }
    return 0;
}

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