Submission #959398

#	Time	Username	Problem	Language	Result	Execution time	Memory
959398		josanneo22	Cyberland (APIO23_cyberland)	C++17	100 / 100	328 ms	123728 KiB

cyberland

#include <bits/stdc++.h>
using namespace std;

struct dsu {
	vector<int> fa, sz;
	dsu(int n) {
		fa.resize(n + 10);
		iota(fa.begin(), fa.end(), 0);
		sz.assign(n + 10, 1);
	}
	int find(int x) {
		while (x != fa[x]) x = fa[x] = fa[fa[x]];
		return x;
	}
	bool merge(int x, int y) {
		int px = find(x), py = find(y);
		if (px == py) return false;
		if (sz[py] > sz[px]) swap(px, py);
		sz[px] += sz[py]; fa[py] = px;
		return true;
	}
	bool same(int x, int y) {
		int px = find(x), py = find(y);
		return px == py;
	}
};


#include "cyberland.h"
#define ld long double
double solve(int N, int M, int K, int H, vector<int> fir, vector<int> sec, vector<int> co, vector<int> arr) {
	K = min(K, 69);
	vector<vector<pair<int,int>>> g(N);
	dsu ds(N);
	for (int i = 0; i < M; i++) {
		if (fir[i] != H && sec[i] != H) ds.merge(fir[i], sec[i]);
		g[fir[i]].push_back(make_pair(co[i], sec[i]));
		g[sec[i]].push_back(make_pair(co[i], fir[i]));
	}
	vector<ld> pwr(K + 1, 1);
	for (int i = 1; i <= K; i++) {
		pwr[i] = pwr[i - 1] / 2;
	}
	arr[0] = 0;
	vector<vector<ld>> dist(K + 1, vector<ld>(N, 1e18));
	using node = tuple<ld, int, int>;
	priority_queue<node, vector<node>, greater<node>> pq;
	auto enq = [&](int k, int x, ld d) {
		if (dist[k][x] > d) {
			dist[k][x] = d;
			pq.push({ d,k,x });
		}
	};
	enq(K, H, 0);
	while (pq.size()) {
		auto [d, k, x] = pq.top(); pq.pop();
		if (dist[k][x] < d) continue;
		if (arr[x] == 0) return (double)d;
		for (auto& [c, v] : g[x]) {
			if (ds.find(v) != ds.find(0)) continue;
			enq(k, v, d + c * pwr[K - k]);
			if (arr[x] == 2 && k > 0) enq(k - 1, v, d + c * pwr[K - k + 1]);
		}
	}
	return (double)-1;
}

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