Submission #804431

#	Time	Username	Problem	Language	Result	Execution time	Memory
804431		MadokaMagicaFan	Cyberland (APIO23_cyberland)	C++17	15 / 100	3062 ms	9212 KiB

cyberland

#include "bits/stdc++.h"
using namespace std;
using ll = long long;
using ld = long double;
#define sz(v) ((int)(v).size())
#define pb push_back

const int N = 1e5;
vector<array<ll, 2>> adj[N];
bitset<N> v, ps;
ll mind1[N], mind2[N], sme[N];
ll inf = 1e18;

void
dfs(int x, int h) {
	if (x == h) return;
	if (ps[x]) return;
	ps[x] = 1;

	for (auto u : adj[x])
		dfs(u[0], h);
}

double
solve(int n, int m, int k, int h, vector<int> x, vector<int> y, vector<int> c, vector<int> arr)
{
	for (int i = 0; i < n; ++i) {
		sme[i] = inf;
		mind2[i] = inf;
		mind1[i] = 0;
		while (sz(adj[i]))
			adj[i].pop_back();
	}
	v = 0;

	if (h == 0) return 0;
	for (int i = 0; i < m; ++i) {
		adj[x[i]].pb({y[i], c[i]});
		if (y[i] != h)
			sme[x[i]] = min(sme[x[i]], (ll)c[i]);
		adj[y[i]].pb({x[i], c[i]});
		if (x[i] != h)
			sme[y[i]] = min(sme[y[i]], (ll)c[i]);
	}

	dfs(0, h);
	priority_queue<array<ll, 2>> q;
	for (int i = 1; i < n; ++i) {
		if (arr[i] == 0 && ps[i]) {
			q.push({0, i});
			mind1[i] = 0;
		}
		else
			mind1[i] = inf;
	}
	q.push({0, 0});

	while (sz(q)) {
		auto u = q.top();
		q.pop();
		if (v[u[1]]) continue;
		if (u[1] == h) continue;
		v[u[1]] = 1;

		for (auto x : adj[u[1]]) {
			if (mind1[u[1]]+ x[1] < mind1[x[0]]) {
				mind1[x[0]] = mind1[u[1]]+ x[1];
				q.push({-mind1[x[0]], x[0]});
			}
		}
	}

	if (mind1[h] > 1e17) return -1;

	long double ans = mind1[h];
	while (sz(q)) q.pop();
	mind2[h] = 0;
	q.push({0, h});

	v = 0;
	while (sz(q)) {
		auto u = q.top();
		q.pop();
		if (v[u[1]]) continue;
		v[u[1]] = 1;

		for (auto x : adj[u[1]]) {
			if (mind2[u[1]]+ x[1] < mind2[x[0]]) {
				mind2[x[0]] = mind2[u[1]]+ x[1];
				q.push({-mind2[x[0]], x[0]});
			}
		}
	}

	for (int i = 1; i < n; ++i) {
		if (mind1[i] > 1e17) continue;
		if (arr[i] != 2) continue;
		long double v = mind1[i];
		long double z = sme[i];
		v = v / ((ld)2);
		int c = min(k-1, 100);
		if (sme[i] >= 1e17) c = 0;
		while (c && z * ((ld) 2) <= v) {
			v = v / ((ld) 2) + z;
		}

		z = mind2[i];
		ans = min(ans, z + v);
	}


	return ans;
}

• Subtask 1: 0 / 5
• Subtask 2: 8 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 19
• Subtask 5: 7 / 7
• Subtask 6: 0 / 16
• Subtask 7: 0 / 29
• Subtask 8: 0 / 3