Submission #311948

#	Time	Username	Problem	Language	Result	Execution time	Memory
311948		Eric_hoo	Stations (IOI20_stations)	C++14	100 / 100	1041 ms	1160 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>

using namespace std;

vector <int> id; int TOT;
vector <int> from[1010];

void dfs(int x, int last, int dep) {
	if (dep & 1) {
		id[x] = TOT++;
		for (int i = 0; i < from[x].size(); i++) {
			int v = from[x][i];
			if (v == last) continue;
			dfs(v, x, dep + 1);
		}
	} else {
		for (int i = 0; i < from[x].size(); i++) {
			int v = from[x][i];
			if (v == last) continue;
			dfs(v, x, dep + 1);
		}
		id[x] = TOT++;
	}
}

vector <int> label(int n, int k, vector <int> X, vector <int> Y) {
	for (int i = 0; i < n; i++) {
		from[i].clear();
	}
	for (int i = 0; i < n - 1; i++) {
		from[X[i]].push_back(Y[i]);
		from[Y[i]].push_back(X[i]);
	}
	id.resize(n), TOT = 0, dfs(0, 0, 1);
	return id;
}

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

Compilation message (stderr)

stations.cpp: In function 'void dfs(int, int, int)':
stations.cpp:12:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |   for (int i = 0; i < from[x].size(); i++) {
      |                   ~~^~~~~~~~~~~~~~~~
stations.cpp:18:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |   for (int i = 0; i < from[x].size(); i++) {
      |                   ~~^~~~~~~~~~~~~~~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:42:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |   for (int i = 0; i + 1 < c.size(); i++) {
      |                   ~~~~~~^~~~~~~~~~

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