#include<bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using mint=modint998244353; //1000000007;
using ll=long long;
using pp=pair<int,int>;
#define sr string 
#define vc vector
#define fi first
#define se second
#define rep(i,n) for(int i=0;i<(int)n;i++)
#define pb push_back
#define all(v) v.begin(),v.end()
#define pque priority_queue
#define bpc(a) __builtin_popcount(a)
int main(){
  int n,k;cin>>n>>k;
  vc v(n,vc<pp>(0));
  rep(i,n-1){
    int a,b,c;cin>>a>>b>>c; a--;b--;
    v[a].pb({b,c}); v[b].pb({a,c});
  }
  int ans=0,ansx=0;
  vc<pp>x;
  auto f=[&](auto f,int a,int p)->int{
    int res=0;
    if(v[a].size()==1)res=1;
    for(auto [au,c]:v[a])if(au!=p){
      int t=f(f,au,a);
      x.pb({c,c*t});
      ansx+=c*t;
      res+=t;
    }
    return res;
  };
  f(f,0,-1);
  vc<int>dp(k+1,0); 
  for(auto [a,b]:x){
    auto pre=dp;
    rep(i,k)if(i+a<=k)dp[i+a]=max(dp[i+a],pre[i]+b);
  }
  rep(i,k+1)ans=max(ans,dp[i]);
  cout<<ans+ansx;
}