Submission #985700

#	Time	Username	Problem	Language	Result	Execution time	Memory
985700		siewjh	Cyberland (APIO23_cyberland)	C++17	97 / 100	3030 ms	312300 KiB

cyberland

#include "cyberland.h"
#include <bits/stdc++.h>
using namespace std;
typedef long double ld;
typedef tuple<ld, int, int> t3;
const int MAXN = 100005;
const ld inf = 1e18;
vector<pair<int, int>> adj[MAXN];
bool vis[MAXN];
ld dist[MAXN][70];

double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr){
	K = min(K, 68);
	for (int i = 0; i < N; i++){
		adj[i].clear(); vis[i] = 0;
		for (int j = 0; j <= K; j++) dist[i][j] = inf;
	}
	for (int i = 0; i < M; i++){
		adj[x[i]].push_back({y[i], c[i]});
		adj[y[i]].push_back({x[i], c[i]});
	}
	priority_queue<t3, vector<t3>, greater<t3>> pq;
	pq.push({0, 0, 0}); dist[0][0] = 0;
	queue<int> q;
	q.push(0); vis[0] = 1;
	while (!q.empty()){
		int x = q.front(); q.pop();
		if (x == H) continue;
		if (arr[x] == 0){
			pq.push({0, x, 0}); dist[x][0] = 0;
		}
		for (auto &[nn, nd] : adj[x])
			if (!vis[nn]){
				q.push(nn); vis[nn] = 1;
			}
	}
	while (!pq.empty()){
		ld d; int x, use; tie(d, x, use) = pq.top(); pq.pop();
		if (dist[x][use] != d) continue;
		if (x == H) continue;
		for (auto &[nn, nd] : adj[x]){
			ld fd = d + nd;
			if (dist[nn][use] > fd){
				dist[nn][use] = fd;
				pq.push({dist[nn][use], nn, use});
			}
			if (arr[nn] == 2 && use < K && dist[nn][use + 1] > fd / 2){
				dist[nn][use + 1] = fd / 2;
				pq.push({dist[nn][use + 1], nn, use + 1});
			}
		}
	}
	ld ans = inf;
	for (int use = 0; use <= K; use++) ans = min(ans, dist[H][use]);
	return (ans == inf ? -1 : ans);
}

• 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: 0 / 3