Submission #851688

#	Time	Username	Problem	Language	Result	Execution time	Memory
851688		yellowtoad	Stations (IOI20_stations)	C++17	100 / 100	594 ms	1680 KiB

stations

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

vector<int> path, edge[1010];

void dfs(int u, int v, int d) {
	if (d%2 == 0) path.push_back(u);
	for (int i = 0; i < edge[u].size(); i++) if (edge[u][i] != v) dfs(edge[u][i],u,d+1);
	if (d%2) path.push_back(u);
}

std::vector<int> label(int n, int _, std::vector<int> u, std::vector<int> v) {
	path.clear();
	vector<int> labels(n);
	for (int i = 0; i < n; i++) edge[i].clear();
	for (int i = 0; i < n-1; i++) {
		edge[u[i]].push_back(v[i]);
		edge[v[i]].push_back(u[i]);
	}
	dfs(0,-1,0);
	for (int i = 0; i < n; i++) labels[path[i]] = i;
	return labels;
}

int find_next_station(int s, int t, std::vector<int> c) {
	if (c[0] > s) {
		if (t < s) return c[c.size()-1];
		for (int i = 0; i < c.size()-1; i++) if (t <= c[i]) return c[i];
		return c[c.size()-1];
	} else {
		if (t > s) return c[0]; 
		for (int i = c.size()-1; i >= 1; i--) if (t >= c[i]) return c[i];
		return c[0];
	}
}

Compilation message (stderr)

stations.cpp: In function 'void dfs(int, int, int)':
stations.cpp:11:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |  for (int i = 0; i < edge[u].size(); i++) if (edge[u][i] != v) dfs(edge[u][i],u,d+1);
      |                  ~~^~~~~~~~~~~~~~~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:31:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |   for (int i = 0; i < c.size()-1; i++) if (t <= c[i]) return c[i];
      |                   ~~^~~~~~~~~~~~

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