Submission #840176

#	Time	Username	Problem	Language	Result	Execution time	Memory
840176		TranGiaHuy1508	Longest Trip (IOI23_longesttrip)	C++17	40 / 100	13 ms	336 KiB

longesttrip

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

#include "longesttrip.h"

namespace {
	vector<int> D3(int N){
		vector<int> res(N);
		iota(res.begin(), res.end(), 0);
		return res;
	}

	vector<int> D2(int N){
		bool edge1 = are_connected({0}, {1});
		bool edge2 = are_connected({1}, {2});
		bool edge3 = are_connected({2}, {0});

		deque<int> res;
		if (edge1 && edge2){
			res.push_back(0); res.push_back(1); res.push_back(2);
		}
		else if (edge2 && edge3){
			res.push_back(1); res.push_back(2); res.push_back(0);
		}
		else{
			res.push_back(2); res.push_back(0); res.push_back(1);
		}

		for (int i = 3; i < N; i++){
			bool e1 = are_connected({i}, {res.front()});

			if (e1) res.push_front(i);
			else res.push_back(i);
		}

		vector<int> vres(res.begin(), res.end());
		return vres;
	}

	vector<int> half(int N){
		deque<int> path1, path2;
		path1.push_back(0); path2.push_back(1);

		for (int i = 2; i < N; i++){
			if (are_connected({i}, {path1.back()})) path1.push_back(i);
			else if (are_connected({i}, {path2.front()})) path2.push_front(i);
			else{
				path1.insert(path1.end(), path2.begin(), path2.end());
				path2.clear(); path2.push_back(i);
			}
		}

		vector<int> v1(path1.begin(), path1.end());
		vector<int> v2(path2.begin(), path2.end());
		
		if (v1.size() < v2.size()) return v2;
		return v1;
	}
}

vector<int> longest_trip(int N, int D){
	if (D == 3){
		return D3(N);
	}
	if (D == 2){
		return D2(N);
	}

	return half(N);
}

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 25 / 25
• Subtask 4: 0 / 60