#include < iostream >
using   namespace  std;

int  N,k;
int  ch1[ 110 ],ch2[ 110 ],val[ 110 ];
int  f[ 110 ][ 110 ];
int  vis[ 110 ];
inline  int  max( int  x, int  y){
     return  x > y ? x:y;
}
void  treedp( int  x){
     int  root,c1 = 0 ,c2;
    vis[x] = 1 ;
     for ( int  i = 1 ;i < N; ++ i)
         if (ch1[i] == x || ch2[i] == x){
            root = ch1[i] + ch2[i] - x;
             if (vis[root])
                f[x][ 1 ] = val[i];
             else {
                 if ( ! c1) c1 = root;  else  c2 = root;
                treedp(root);
            }
        }
     if (c1)
     for ( int  i = 1 ;i <= k; ++ i)
         for ( int  j = 0 ;j < i; ++ j)
            f[x][i] = max(f[x][i],f[x][ 1 ] + f[c1][j] + f[c2][i - 1 - j]);
}
int  main()
{
    cin >> N >> k;
    k ++ ;
     for ( int  i = 1 ;i < N; ++ i)
        cin >> ch1[i] >> ch2[i] >> val[i];
    memset(f, 0 , sizeof (f));
    memset(vis, 0 , sizeof (vis));
    treedp( 1 );
    cout << f[ 1 ][k] << endl;
     return   0 ;
}