Submission #413252

#	Time	Username	Problem	Language	Result	Execution time	Memory
413252		SuhaibSawalha1	Stations (IOI20_stations)	C++17	8 / 100	934 ms	616 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
 
vector<vector<int>> adj;
vector<int> lab;
int cnt;
 
void dfs (int u, int p = -1) {
	for (int v : adj[u]) {
		if (v ^ p) {
			dfs(v, u);
		}
	}
	lab[u] = cnt++;
}

bool subtask2 () {
	for (int i = 0; i < (int)adj.size(); ++i) {
		vector<int> y{(i - 1) / 2, 2 * i + 1, 2 * i + 2};
		if (!i) {
			y.erase(y.begin());
		}
		sort(adj[i].begin(), adj[i].end());
		while (y.size() > adj[i].size()) {
			y.pop_back();
		}
		if (y != adj[i]) {
			return 0;
		}
	}
	return 1;
}
 
vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	adj.assign(n, {});
	lab.resize(n);
	cnt = 0;
	for (int i = 0; i < n - 1; ++i) {
		adj[u[i]].push_back(v[i]);
		adj[v[i]].push_back(u[i]);
	}
	if (!subtask2()) {
		for (int i = 0; i < n; ++i) {
			if (adj[i].size() == 1) {
				dfs(i);
				break;
			}
		}
		return lab;
	}
	iota(lab.begin(), lab.end(), 0);
	return lab;
}
 
int find_next_station(int s, int t, vector<int> c) {
	sort(c.begin(), c.end());
	vector<int> y{(s - 1) / 2, 2 * s + 1, 2 * s + 2};
	if (!s) {
		y.erase(y.begin());
	}
	while (y.size() > c.size()) {
		y.pop_back();
	}
	if (y != c) {
		return s - (t < s) + (t > s);
	}
	int e = t;
	while (e) {
		int p = (e - 1) / 2;
		if (p == s) {
			return e;
		}
		e = p;
	}
	return (s - 1) / 2;
}

• Subtask 1: 0 / 5
• Subtask 2: 8 / 8
• Subtask 3: 0 / 16
• Subtask 4: 0 / 10
• Subtask 5: 0 / 61