제출 #98138

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
98138		luciocf	Chase (CEOI17_chase)	C++14	50 / 100	4096 ms	185336 KiB

chase

#include <bits/stdc++.h>

using namespace std;

const int maxn = 1e5+10;
const int maxv = 110;

typedef long long ll;

int n, c;
int num[maxn];

ll soma[maxn], dp[maxn][maxv][2];

vector<int> grafo[maxn];

void dfs(int u, int p)
{
	for (auto v: grafo[u])
	{
		if (v == p) continue;

		ll x = (ll)soma[v]-(ll)num[u];

		for (int i = 0; i <= c; i++)
		{
			dp[v][i][0] = max(dp[u][i][0], dp[u][i][1]);

			if (!i) continue;

			dp[v][i][1] = dp[u][i-1][0];
			dp[v][i][1] = x+max(dp[v][i][1], dp[u][i-1][1]);
		}

		dfs(v, u);
	}
}

ll solve_big(void)
{
	dp[1][1][1] = soma[1];
	dfs(1, 0);

	ll ans = 0LL;

	for (int i = 1; i <= n; i++)
		for (int j = 0; j <= c; j++)
			ans = max({ans, dp[i][j][0], dp[i][j][1]});

	return ans;
}

int main(void)
{
	ios::sync_with_stdio(false); cin.tie(0);

	cin >> n >> c;

	for (int i = 1; i <= n; i++)
		cin >> num[i];

	for (int i = 1; i < n; i++)
	{
		int u, v;
		cin >> u >> v;

		grafo[u].push_back(v); grafo[v].push_back(u);
	}

	for (int u = 1; u <= n; u++)
		for (auto v: grafo[u])
			soma[u] += (ll)num[v];

	if (n > 1000)
	{
		cout << solve_big() << "\n";
		return 0;
	}

	ll ans = 0LL;

	for (int i = 1; i <= n; i++)
	{
		memset(dp, 0, sizeof dp);

		dp[i][1][1] = soma[i];

		dfs(i, 0);

		for (int j = 1; j <= n; j++)
			for (int l = 0; l <= c; l++)
				ans = max({ans, dp[j][l][0], dp[j][l][1]});
	}

	cout << ans << "\n";
}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 20
• Subtask 3: 30 / 30
• Subtask 4: 0 / 30