Submission #966541

#	Time	Username	Problem	Language	Result	Execution time	Memory
966541		Darren0724	Fun Tour (APIO20_fun)	C++17	100 / 100	202 ms	22756 KiB

fun

#include "fun.h"
#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define all(x) x.begin(),x.end()
const int N=100005;
int cntid=0;
const int INF=1e9;
vector<int> ans;
priority_queue<pair<int,int>> pq[4];
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
vector<int> createFunTour(int n, int q) {
	ans.clear();
	int c1=0;
	int need=(n+1)/2;
	int mn=INF;
	for(int i=0;i<n-1;i++){
		int t=attractionsBehind(0, i);
		if(t>=need&&t<mn){
			mn=t;
			c1=i;
		}
	}
	vector<int> r;
	vector<int> dis0(N,0);
	for(int i=0;i<n;i++){
		dis0[i]=hoursRequired(c1,i);
		if(dis0[i]==1){
			r.push_back(i);
		}
	}
	int rsz=r.size()-1;
	assert(rsz<=2);
	vector<vector<int>> dis(rsz,vector<int>(N));
	vector<int> vis(N);
	for(int i=0;i<rsz;i++){
		for(int j=0;j<n;j++){
			dis[i][j]=hoursRequired(r[i],j);
		}
	}
	for(int i=0;i<n;i++){
		if(i==c1)continue;
		int p=-1;
		for(int j=0;j<rsz;j++){
			if(dis[j][i]<dis0[i]){
				p=j;break;
			}
		}
		if(p==-1)p=rsz;
		pq[p].push({dis0[i],i});
	}
	cntid=4;
	int last=0;
	int left=n-1;int mer=0;
	for(int i=1;i<n;i++){
		array<int,3> p={-1,-1,-1};
		for(int j=0;j<cntid;j++){
			if(j==last||pq[j].size()==0)continue;
			p=max(p,array<int,3>{pq[j].top().first,(int)pq[j].size(),j});
		}
		pair<int,int> mx={-1,-1};
		for(int j=0;j<cntid;j++){
			mx=max(mx,{(int)pq[j].size(),j});
		}
		if(mer==0&&(left-mx.first)<mx.first){
			mer=1;
			if(last!=mx.S&&(!pq[last].empty()&&!pq[3-last-mx.S].empty())&&pq[last].top().F<pq[3-last-mx.S].top().first){
				last=3-last-mx.second;
				ans.push_back(pq[last].top().second);
				pq[last].pop();	
				i++;
			}
			if(last==mx.S)last=(last+1)%3;
			while(!pq[last].empty()){
				pq[3-last-mx.S].push(pq[last].top());
				pq[last].pop();
			}
			//assert(last!=mx.second);
				p[2]=mx.second;
		}

		last=(p[2]==-1?last:p[2]);
		//assert(last!=-1&&pq[last].size()>0);
		auto [dis1,idx]=pq[last].top();
		pq[last].pop();
		ans.push_back(idx);
		left--;
	}
	ans.push_back(c1);
	// for(int j:ans){
	// 	cout<<j<<' ';
	// }
	// cout<<endl;
  	return ans;
}
/*
46 100000
0 1
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12
12 13
13 14
14 15
0 16
16 17 
17 18
18 19
19 20
20 21
21 22
22 23
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24 25
25 26
26 27
27 28
28 29
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0 31
31 32
31 33
32 34
32 35
33 36
33 37
34 38
34 39
35 40
35 41
36 42 
36 43
37 44
37 45
*/

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 21 / 21
• Subtask 4: 19 / 19
• Subtask 5: 34 / 34