#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = std::int_fast64_t;
using std::cout;
using std::cerr;
using std::endl;
using std::cin;

template<typename T>
std::vector<T> make_v(size_t a){return std::vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

int main() {
	int n, k; scanf("%d%d", &n, &k);
	std::vector<int> a(n - 1), b(n - 1), c(n - 1);
	std::vector<std::vector<int>> g(n);
	for(int i = 0; i < n - 1; i++) {
		scanf("%d%d%d", &a[i], &b[i], &c[i]);
		a[i]--; b[i]--;

		g[a[i]].push_back(i);
		g[b[i]].push_back(i);
	}

	i64 sum = 0;
	std::vector<int> size(n), p(n - 1), q(n - 1);
	auto solve = [&](auto&& solve, int v, int par) -> int {
		for(int id: g[v]) {
			int to = a[id] ^ b[id] ^ v;
			if(to == par) continue;
			int ret = solve(solve, to, v);
			size[v] += ret;

			p[id] = c[id];
			q[id] = ret * c[id];
			sum += ret * c[id];
		}
		if(size[v] == 0) return size[v] = 1;
		return size[v];
	}; solve(solve, 0, -1);

	std::vector<int> dp(k + 1, 0);
	for(int i = 0; i < n - 1; i++) {
		for(int j = std::max(0, k - p[i]); j >= 0; j--) {
			dp[j + p[i]] = std::max(dp[j + p[i]], dp[j] + q[i]);
		}
	}
	printf("%d\n", *std::max_element(begin(dp), end(dp)) + sum);
	return 0;
}