import java.util.*;
import java.io.*;

public class Main {
    static int m;
    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String[] first = br.readLine().split(" ", 2);
        int n = Integer.parseInt(first[0]);
        m = Integer.parseInt(first[1]) + 1;
        Node[] tree = new Node[n];
        for (int i = 0; i < n; i++) {
            tree[i] = new Node(i, Integer.parseInt(br.readLine()));
        }
        for (int i = 0; i < n - 1; i++) {
            String[] line = br.readLine().split(" ", 3);
            int a = Integer.parseInt(line[0]);
            int b = Integer.parseInt(line[1]);
            int c = Integer.parseInt(line[2]);
            tree[a].add(tree[b], c);
            tree[b].add(tree[a], c);
        }
        int[] arr = tree[0].getArray(null);
        Arrays.sort(arr);
        System.out.println(arr[m - 1]);
  }
  
  static void printArrray(int[] arr) {
      StringBuilder sb = new StringBuilder();
      for (int x : arr) {
          sb.append(x).append(" ");
      }
      System.out.println(sb);
  }
   
   static class Node {
       int id;
       HashMap<Node, Integer> paths = new HashMap<>();
       int[] costs = new int[m];
       
       public Node(int id, int cost) {
           this.id = id;
           costs[0] = cost;
       }
       
       public void add(Node n, int cost) {
           paths.put(n, cost);
       }
       
       public int[] getArray(Node parent) {
           if (parent != null) {
                paths.remove(parent);
           }
           for (Map.Entry<Node, Integer> p : paths.entrySet()) {
               int[] tmp = new int[m];
               int[] child = p.getKey().getArray(this);
               int added = p.getValue() * 2;
               for (int i = 0; i < m - added; i++) {
                   for (int j = 0; j < m - i - added; j++) {
                       tmp[i + j + added] = Math.max(tmp[i + j + added] , costs[i] + child[j]);
                   }
               }
               for (int i = 0; i < m; i++) {
                   costs[i] = Math.max(costs[i], tmp[i]);
               }
           }
           return costs;
       }
       
       public int hashCode() {
           return id;
       }
       
       public boolean equals(Object o) {
           Node n = (Node) o;
           return id == n.id;
       }
   }
}