Submission #434453

#	Time	Username	Problem	Language	Result	Execution time	Memory
434453		arayi	Stations (IOI20_stations)	C++17	100 / 100	1051 ms	784 KiB

stations

#include "stations.h"
#include <iostream>
#include <algorithm>
#include <vector>
#define ad push_back
using namespace std;

const int N = 1010;
int n;
vector<int> g[N], l;
vector<pair<int, int> > a;
int xr[N], ti;
void dfs(int v, int par)
{
	ti++;
	if(xr[v]%2==0) a.ad({ti,v});
	for(auto p : g[v])
	{
		if(p==par) continue;
		xr[p]=1+xr[v];
		dfs(p,v);
	}
	ti++;
	if(xr[v]%2==1) a.ad({ti, v});
}
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
	::n=n;
	l.clear(), a.clear();
	for (int i = 0; i < n; i++) g[i].clear(),xr[i]=0;
	ti=0;
	l.resize(n);
	for (int i = 0; i < n - 1; i++) {
		g[u[i]].ad(v[i]);
		g[v[i]].ad(u[i]);
	}
	dfs(0, 0);
	sort(a.begin(), a.end());
	for (int i = 0; i < a.size(); i++) l[a[i].second] = i;
	return l;
}

int find_next_station(int s, int t, std::vector<int> c) 
{
	if(c.size() == 1) return c[0];
	sort(c.begin(), c.end());
	if(s < c[0])
	{
		int nx = s;
		for(auto p : c)
		{
			if(t > nx && t <= p) return p;
			nx = p;
		}
		return c.back();
	}
	else
	{
		int nx = c[1];
		for (int i = 2; i < c.size(); i++)
		{
			if(t >= nx && t < c[i]) return nx;
			nx = c[i];
		}
		if(t >= nx && t < s) return nx;
		return c[0];
	}
}

Compilation message (stderr)

stations.cpp: In function 'std::vector<int> label(int, int, std::vector<int>, std::vector<int>)':
stations.cpp:38:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |  for (int i = 0; i < a.size(); i++) l[a[i].second] = i;
      |                  ~~^~~~~~~~~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:59:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |   for (int i = 2; i < c.size(); i++)
      |                   ~~^~~~~~~~~~

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