Submission #581892

#	Time	Username	Problem	Language	Result	Execution time	Memory
581892		joelau	Stations (IOI20_stations)	C++14	100 / 100	1319 ms	860 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>
using namespace std;

vector<int> lst[1005], ans;
int cnt = 0;

void dfs (int x, int p, int d) {
	if (d % 2 == 0) ans[x] = cnt++;
	for (int v: lst[x]) if (v != p) dfs(v,x,d+1);
	if (d % 2 == 1) ans[x] = cnt++;
}

vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	for (int i = 0; i < n; ++i) lst[i].clear();
	for (int i = 0; i < n-1; ++i) lst[u[i]].push_back(v[i]), lst[v[i]].push_back(u[i]);
	ans.assign(n,0);
	cnt = 0;
	dfs(0,-1,0);
	return ans;
}

int find_next_station(int s, int t, vector<int> c) {
	if (s < c[0]) {
		if (t < s || t > c.back()) return c.back();
		else return *lower_bound(c.begin(),c.end(),t);
	}
	else {
		if (t < c.front() || t > s) return c.front();
		else return *prev(upper_bound(c.begin(),c.end(),t));
	}
}

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