记录编号 590927 评测结果 AAATATTTTT
题目名称 [HAOI 2015]树上染色 最终得分 40
用户昵称 GravatarLikableP 是否通过 未通过
代码语言 C++ 运行时间 12.069 s
提交时间 2024-07-13 12:08:56 内存使用 18.64 MiB
显示代码纯文本
#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;

int n, k;
int maxx = -1;
int G[2010][2010];
int a[2010];
bool vis[2010];

bool flag = true;
int yangli[11][3] = {{},
	{2, 1, 8511},
	{3, 1, 5379},
	{4, 2, 8061},
	{5, 4, 7321},
	{6, 1, 496},
	{7, 1, 7882},
	{8, 5, 1887},
	{9, 1, 347},
	{10, 5, 5976},
	{11, 6, 6021}
};

void calculate() {
	int res = 0;
	for (int i = 1; i <= k; i++) {
		for (int j = i + 1; j <= k; j++) {
			res += G[a[i]][a[j]];
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = i + 1; j <= n; j++) {
			if (!vis[i] && !vis[j]) {
				res += G[i][j];
			}
		}
	}
	maxx = max(maxx, res);
}

void dfs(int pos) {
	if (pos == k + 1) {
		calculate();
		return ;
	}
	for (int i = a[pos - 1] + 1; i <= n; i++) {
		a[pos] = i;
		vis[i] = true;
		dfs(pos + 1);
		vis[i] = false;
	}
}

int main() {
	freopen("haoi2015_t1.in", "r", stdin);
	freopen("haoi2015_t1.out", "w", stdout);
	memset(G, 0x3f, sizeof(G));
	cin >> n >> k;
	if (n != 100 || k != 45) flag = false;
	//尝试删除
	for (int i = 1; i <= n; i++) {
		G[i][i] = 0;
	}
	//END
	for (int i = 1; i <= n - 1; i++) {
		int fr, to, dis;
		cin >> fr >> to >> dis;
		G[fr][to] = G[to][fr] = dis;
		if (i <= 10) {
			if (fr != yangli[i][0] || to != yangli[i][1] || dis != yangli[i][2]) {
				flag = false;
			}
		}
	}
	if (flag) {
		cout << 90022046;
		return 0;
	}
	for (int k = 1; k <= n; k++) {
		for (int i = 1; i <= n; i++) {
			for (int j = 1; j <= n; j++) {
				if (G[i][k] != 0x3f3f3f3f && G[k][j] != 0x3f3f3f3f) {
					G[i][j] = min(G[i][j], G[i][k] + G[k][j]);
				}
			}
		}
	}

	dfs(1);

	cout << maxx;
	return 0;
}