Submission #990267

#	Time	Username	Problem	Language	Result	Execution time	Memory
990267		PoPularPlusPlus	Stations (IOI20_stations)	C++17	100 / 100	677 ms	1308 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb(x) push_back(x)
#define mp(x,y) make_pair(x,y)
#define all(x) x.begin(),x.end()
#define vf first 
#define vs second

const int N = 1003;

vector<int> adj[N]; 
int col[N],tin[N] , tout[N] , timer;

void dfs(int node ,int par ,int c){
	col[node] = c;
	int c_next = (c + 1)%2;
	tin[node] = timer++;

	for(int i : adj[node]){
		if(i != par){
			dfs(i , node , c_next);
		}
	}

	tout[node] = timer++;
}

vector<int> label(int n, int k, vector<int> u, vector<int> v){

	for(int i = 0; i < n - 1; i++){
		adj[u[i]].pb(v[i]);
		adj[v[i]].pb(u[i]);
	}
	timer=0;
	dfs(0,0,0);

	vector<int> labels(n);
	for(int i = 0; i < n; i++){
		if(col[i] == 0)labels[i] = tin[i];
		else labels[i] = tout[i];
	}

	map<int,int> m;
	for(int i = 0; i < n; i++){
		m[labels[i]] = 1;
	}

	int val[2 * n + 5];
	int cur = 0;
	for(auto i : m){
		val[i.vf] = cur++;
	}

	for(int i = 0; i < n; i++){
		labels[i] = val[labels[i]];
		//cout << labels[i] << ' ';
	}

	for(int i = 0; i <= n; i++){
		adj[i].clear();
	}
	
	return labels;
}

int find_next_station(int s, int t, vector<int> c) {
	sort(all(c));
	if(s == 0){
		int prev = 0;
		for(int i : c){
			if(t >= prev && t <= i){
				return i;
			}
		}
	}
	else {
		int col;
		if(c[0] > s){
			col = 0;
		}
		else col = 1;
		int par;
		if(col == 0){
			par = c.back();
		}
		else par = c[0];

		if(col == 0){
			int prev = s;
			for(int i = 0; i < c.size()-1; i++){
				if(t >= s && t <= c[i]){
					return c[i];
				}
				prev = c[i] + 1;
			}
			return par;
		}
		else {
			for(int i = 1; i < c.size()-1; i++){
				if(t >= c[i] && t < c[i + 1]){
					return c[i];
				}
			}
			if(t >= c.back() && t <= s){
				return c.back();
			}
			return par;
		}
	}
}

Compilation message (stderr)

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:92:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   92 |    for(int i = 0; i < c.size()-1; i++){
      |                   ~~^~~~~~~~~~~~
stations.cpp:91:8: warning: variable 'prev' set but not used [-Wunused-but-set-variable]
   91 |    int prev = s;
      |        ^~~~
stations.cpp:101:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  101 |    for(int i = 1; i < c.size()-1; i++){
      |                   ~~^~~~~~~~~~~~
stations.cpp:112:1: warning: control reaches end of non-void function [-Wreturn-type]
  112 | }
      | ^

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