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

public class Main {
    static int[] values;
    static int m;
    static ArrayList<HashMap<Integer, Integer>> graph = new ArrayList<>();
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        m = sc.nextInt();
        values = new int[n];
        for (int i = 0; i < n; i++) {
            values[i] = sc.nextInt();
            graph.add(new HashMap<>());
        }
        for (int i = 0; i < n - 1; i++) {
            int a = sc.nextInt();
            int b = sc.nextInt();
            int c = sc.nextInt();
            graph.get(a).put(b, c);
            graph.get(b).put(a, c);
        }
        TreeMap<Integer, Integer> ans = getMap(0, 0);
        System.out.println(ans.lastEntry().getValue());
    }
    
    static TreeMap<Integer, Integer> getMap(int idx, int p) {
        TreeMap<Integer, Integer> ans = new TreeMap<>();
        ans.put(0, values[idx]);
        for (int x : graph.get(idx).keySet()) {
            if (x == p) {
                continue;
            }
            int add = graph.get(idx).get(x) * 2;
            TreeMap<Integer, Integer> tmp = getMap(x, idx);
            Integer key = Integer.MAX_VALUE;
            while ((key = ans.lowerKey(key)) != null) {
                Integer y = Integer.MAX_VALUE;
                while ((y = tmp.lowerKey(y)) != null) {
                    Integer next = key + y + add;
                    int nValue = ans.get(key) + tmp.get(y);
                    if (next > m) {
                        continue;
                    }
                    if (ans.floorEntry(next).getValue() >= nValue) {
                        continue;
                    }
                    ans.put(next, nValue);
                    while ((next = ans.higherKey(next)) != null) {
                        if (ans.get(next) <= nValue) {
                            ans.remove(next);
                        } else {
                            break;
                        }
                    }
                }
            }
        }
        return ans;
    }
}

class Utilities {
    static String arrayToLineString(Object[] arr) {
        return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));
    }
    
    static String arrayToLineString(int[] arr) {
        return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public int[] nextIntArray() throws Exception {
        return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}