Submission #578554

#	Time	Username	Problem	Language	Result	Execution time	Memory
578554		Vanilla	Stations (IOI20_stations)	C++17	52.32 / 100	940 ms	880 KiB

stations

#include <bits/stdc++.h>
#include "stations.h"
using namespace std;
const int maxn = 1002;
vector <int> ad [maxn];
int ct = 0;

int get_mx(int x) {
	return x / 1000;
}

int get_nd (int x) {
	return x % 1000;
}

bool comp (int a, int b){
	return a % 1000 < b % 1000;
}

int dfs (int u, int p, vector <int> &lb) {
	lb[u] = ct++;
	int mx = 0;
	for (int v: ad[u]) {
		if (v == p) continue;
		mx = max(mx, dfs(v, u, lb));
	}
	mx = max(mx, lb[u]);
	lb[u] += 1000 * mx;
	return mx;
}

vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	vector<int> labels(n);
	ct = 0;
	for (int i = 0; i < n; i++){
		ad[i].clear();
	}
	for (int i = 0; i < n - 1; i++){
		ad[u[i]].push_back(v[i]);
		ad[v[i]].push_back(u[i]);
	}
	dfs(0, -1, labels);
	// for (int i = 0; i < n; i++){
	// 	cout << i << " " << labels[i] << " " << get_nd(labels[i]) << " " << get_mx(labels[i]) << "\n";
	// }
	return labels;
}

int find_next_station(int s, int t, vector<int> c) {
	sort(c.begin(), c.end(), comp);
	if (get_nd(t) < get_nd(s) || get_mx(s) < get_nd(t)) return c[0];
	for (int i = 1; i < c.size(); i++){
		if (get_nd(c[i]) == get_nd(t)) return c[i];
		if (get_nd(c[i]) > get_nd(t)) return c[i-1];
	}
	return c.back();
}

Compilation message (stderr)

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:52:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |  for (int i = 1; i < c.size(); i++){
      |                  ~~^~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 16 / 16
• Subtask 4: 10 / 10
• Subtask 5: 26.3205 / 61