Submission #453228

#	Time	Username	Problem	Language	Result	Execution time	Memory
453228		valerikk	Beads and wires (APIO14_beads)	C++17	28 / 100	1083 ms	1356 KiB

beads

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

typedef long long ll;

const int N = 10010;
const ll INF = 1e18;

int n;
vector<pair<int, ll>> g[N];
ll dp[N][2];

void dfs(int v, int p = -1, ll kek = INF) {
	ll mx = 0, sum = 0;
	for (auto [u, w] : g[v]) {
		if (u != p) {
			dfs(u, v, w);
			sum += dp[u][1];
			mx = max(mx, dp[u][0] - dp[u][1] + kek + w);
		}
	}
	dp[v][0] = sum;
	dp[v][1] = sum + mx;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n;
	for (int i = 0; i < n - 1; ++i) {
		int a, b;
		ll c;
		cin >> a >> b >> c;
		g[a].push_back({b, c});
		g[b].push_back({a, c});
	}
	ll ans = 0;
	for (int i = 1; i <= n; ++i) {
		dfs(i);
		ans = max(ans, dp[i][0]);
	}
	cout << ans << endl;
	return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 15 / 15
• Subtask 3: 0 / 29
• Subtask 4: 0 / 43