8pts WA玄关

#include<bits/stdc++.h>
#define son first
#define val second
using namespace std;
const int N = 110;
vector <pair <int, int> > e[N];
int n, k, dp[N][N], value[N], dep[N], s[N][2], siz[N];
void dfs(int x, int fa)
{
	if (x != 0 && e[x].size() == 1)
	{
		dp[x][0] = value[x];
		return;
	}
	if (s[x][0])
		dfs(s[x][0], x);
	if (s[x][1])
		dfs(s[x][1], x);
	if (s[x][0] && s[x][1])
	{
		for (int i = 0; i <= k; i++)
			for (int j = 0; j <= k - i; j++)
				dp[x][i + j] = max(dp[s[x][0]][i] + dp[s[x][1]][j], dp[x][i + j]);
		for (int i = 0; i <= k - siz[s[x][0]]; i++)
			dp[x][i + siz[s[x][0]]] = max(dp[s[x][1]][i], dp[x][i + siz[s[x][0]]]);
		for (int i = 0; i <= k - siz[s[x][1]]; i++)
			dp[x][i + siz[s[x][1]]] = max(dp[s[x][0]][i], dp[x][i + siz[s[x][1]]]);
		dp[x][min(k, siz[x] - 1)] = max(dp[x][min(k, siz[x] - 1)], 0);
	}
	else if (s[x][0])
	{
		for (int i = 0; i <= k; i++)
			dp[x][i] = max(dp[x][i], dp[s[x][0]][i]);
		dp[x][min(k, siz[x] - 1)] = max(dp[x][min(k, siz[x] - 1)], 0);
	}
	for (int i = 0; i <= k; i++)
		dp[x][i] += value[x];
	return;
}
void build(int x, int fa)
{
	dep[x] = dep[fa] + 1;
	siz[x] = 1;
	if (x != 1 && e[x].size() == 1)
		return;
	int p = 0;
	for (auto i : e[x])
	{
		if (i.son == fa)
			continue;
		s[x][p++] = i.son;
		value[i.son] = i.val;
		build(i.son, x);
		siz[x] += siz[i.son];
	}
	return;
}
int main()
{
	memset(dp, 0xc0, sizeof dp);
	cin >> n >> k;
	for (int i = 1, u, v, w; i < n; i++)
	{
		scanf("%d%d%d", &u, &v, &w);
		e[u].push_back({v, w});
		e[v].push_back({u, w});
	}
	build(1, 0);
	dfs(1, 0);
	printf("%d", dp[1][k]);
	return 0;
}