#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define ALL(v) v.begin(), v.end()
typedef long long ll;

#include <bits/stdc++.h>
using namespace std;

vector<int> G[110];
int dep[110];
int chi[110];
int A[110],B[110],C[110],D[110];
int dp[110][100010];

int dfs(int v,int p,int d){
  dep[v]=d;
  int tmp=0;
  if(G[v].size()==1 && v!=0){
    return chi[v]=1;
  }
  for(auto nv:G[v]){
    if(nv==p) continue;
    tmp+=dfs(nv,v,d+1);
  }
  return chi[v]=tmp;
}

int main(){
  int n,k;
  cin>>n>>k;
  
  int ans=0;
  rep(i,n-1){
    int a,b,c;
    cin>>a>>b>>c;
    a--,b--;
    A[i]=a,B[i]=b,C[i]=c;
    G[a].push_back(b);
    G[b].push_back(a);
  }
  
  dfs(0,-1,0);
  rep(i,n-1){
    if(dep[A[i]]<dep[B[i]]) D[i]=C[i]*chi[B[i]];
    else D[i]=C[i]*chi[A[i]];
    ans+=D[i];
  }
  
  memset(dp,-1,sizeof(dp));
  dp[0][0]=0;
  rep(i,n){
    rep(j,k+1){
      if(dp[i][j]==-1) continue;
      dp[i+1][j]=max(dp[i+1][j],dp[i][j]);
      if(j+C[i]<=k) dp[i+1][j+C[i]]=max(dp[i+1][j+C[i]],dp[i][j]+D[i]);
    }
  }
  int ma=0;
  rep(j,k+1) ma=max(ma,dp[n][j]);
  cout<<ans+ma<<endl;

  return 0;
}