Submission #578575

#	Time	Username	Problem	Language	Result	Execution time	Memory
578575		Vanilla	Stations (IOI20_stations)	C++17	0 / 100	793 ms	668 KiB

stations

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

int get_nd (int x) {
	return x / 2;
}

void dfs (int u, int p) {
	in[u]=ct++;
	int mx = 0;
	for (int v: ad[u]) {
		if (v == p) continue;
		dp[v] = dp[u] + 1;
		dfs(v, u);
	}
	out[u]=ct++;
	
}

vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	vector<int> labels(n);
	vector <int> norm (n);
	ct = 0;
	for (int i = 0; i < n; i++){
		in[i] = out[i] = dp[i] = 0;
		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);
	for (int i = 0; i < n; i++){
		if (dp[i] % 2 == 0) labels[i] = in[i];
		else labels[i] = out[i];
		norm[i] = labels[i];
	}
	sort(norm.begin(), norm.end());
	for (int i = 0; i < n; i++){
		labels[i] = lower_bound(norm.begin(), norm.end(), labels[i]) - norm.begin();
	}

	return labels;
}

int find_next_station(int s, int t, vector<int> c) {
	if (c[0] > s) {
		if (t < s) return c.back();
		auto it = lower_bound(c.begin(), c.end(), t);
		if (it == c.begin()) it--;
		return *it;
	}
	if (t > s) return c[0];
	auto it = upper_bound(c.begin(), c.end(), t);
	if (it != c.begin()) it--;
	return *it;
}

Compilation message (stderr)

stations.cpp: In function 'void dfs(int, int)':
stations.cpp:16:6: warning: unused variable 'mx' [-Wunused-variable]
   16 |  int mx = 0;
      |      ^~

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