Submission #430173

#	Time	Username	Problem	Language	Result	Execution time	Memory
430173		alireza_kaviani	Stations (IOI20_stations)	C++17	100 / 100	1442 ms	876 KiB

stations

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

#define sep			' '

const int MAXN = 1010;
int timer , ans[MAXN];
vector<int> adj[MAXN];

void DFS(int v , int p = -1 , int h = 0){
	if(h % 2 == 0)	ans[v] = timer++;
	for(int u : adj[v]){
		if(u == p)	continue;
		DFS(u , v , h + 1);
	}
	if(h % 2 == 1)	ans[v] = timer++;
}

vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	vector<int> labels(n , 0); timer = 0;
	for (int i = 0; i < n; i++) {
		adj[i].clear(); ans[i] = 0;
	}
	for(int i = 0 ; i < n - 1 ; i++){
		adj[v[i]].push_back(u[i]);
		adj[u[i]].push_back(v[i]);
	}
	DFS(0);
	for(int i = 0 ; i < n ; i++){
		labels[i] = ans[i];
//		cout << i << sep << ans[i] << endl;
	}
	return labels;
}

int SolveSt(int s , int t , vector<int> c){
//	cout << "solveSt " << s << sep << t << sep << c.size() << endl;
	int prv = s;
	for(int u : c){
		if(prv < t && t <= u)	return u;
		prv = u;
	}
	return c.back();
}

int SolveFn(int s , int t , vector<int> c){
//	cout << "SolveFn " << s << sep << t << sep << c.size() << endl;
	int prv = s;
	reverse(c.begin() , c.end());
	for(int u : c){
//		cout << u << endl;
		if(u <= t && t < prv)	return u;
		prv = u;
	}
	return c.back();
}

int find_next_station(int s, int t, vector<int> c) {
//	cout << "query " << s << sep << t << endl;
	if(s < c[0])	return SolveSt(s , t , c);
	if(s > c[0])	return SolveFn(s , t , c);
}

Compilation message (stderr)

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:63:1: warning: control reaches end of non-void function [-Wreturn-type]
   63 | }
      | ^

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