Submission #759628

#	Time	Username	Problem	Language	Result	Execution time	Memory
759628		IvanJ	Cyberland (APIO23_cyberland)	C++17	49 / 100	53 ms	9524 KiB

cyberland

#include "cyberland.h"
#include<bits/stdc++.h>

#define pb push_back
#define x first
#define y second
#define all(a) (a).begin(), (a).end()

using namespace std;

typedef long long ll;
typedef pair<int, int> ii;

const int maxn = 1e5 + 5;
const double inf = 1e18;
double dist[maxn], dist1[maxn];
vector<ii> adj[maxn];
int vis[maxn], change[maxn];
int X;

void reach(int x) {
	if(vis[x] || x == X) return;
	vis[x] = 1;
	for(auto p : adj[x]) 
		reach(p.x);
}

double solve(int N, int M, int K, int H, vector<int> u, vector<int> v, vector<int> c, vector<int> arr) {
	for(int i = 0;i < N;i++) {
		adj[i].clear();
		vis[i] = 0;
		dist[i] = inf;
	}
	
	for(int i = 0;i < M;i++) 
		adj[u[i]].pb({v[i], c[i]}), adj[v[i]].pb({u[i], c[i]});
	
	X = H;
	reach(0);
	for(int i = 0;i < N;i++) 
		if(arr[i] == 0 && vis[i] == 1) dist[i] = 0;
	dist[0] = 0;
	
	for(int k = 0;k <= min(K, 60);k++) {
		set<pair<double, int>> s;
		for(int i = 0;i < N;i++) {
			change[i] = 0;
			dist1[i] = dist[i];
			if(vis[i] == 1) s.insert({dist[i], i});
		}
		
		int flag = 0;
		while(s.size()) {
			auto state = *s.begin();
			s.erase(state);
			int x = state.y;
			if(x == H) continue;
			
			for(auto p : adj[x]) {
				int y = p.x;
				double cost = p.y;
				
				if(dist1[x] + cost == dist1[y] && arr[y] == 2) change[y] = 1, flag = 1;
				if(dist1[x] + cost < dist1[y]) {
					s.erase({dist1[y], y});
					dist1[y] = dist1[x] + cost;
					change[y] = 1, flag = 1;
					s.insert({dist1[y], y});
				}
			}
		}
		
		for(int i = 0;i < N;i++) {
			dist[i] = dist1[i];
			if(arr[i] == 2 && change[i] == 1) dist[i] /= 2.0;
		}
		if(flag == 0) break;
	}
	
	if(dist[H] == inf) return -1;
	return dist[H]; 
}

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