Submission #430221

#	Time	Username	Problem	Language	Result	Execution time	Memory
430221		dreezy	Stations (IOI20_stations)	C++17	0 / 100	6 ms	784 KiB

stations

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

#define ll long long
#define pb push_back

vector<int> labels;
vector<vector<int>> graph;

vector<int> sz;
void dfs1(int n,int p){//calc sizes
	sz[n] = 1;
	for(int adj : graph[n])
	{
		if(adj == p) continue;
		dfs1(adj, n);
		sz[n] += sz[adj];
	}
}

int counter = 0;
void name_subtree(int n, int p){
	labels[n] =counter++;
	for(int adj : graph[n]){
		if(adj == p)
		continue;
		name_subtree(adj, n);
	}
}


vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	counter = 0;
	sz.assign(n, 0);
	labels.assign(n, 0);
	graph.assign( n, vector<int>());
	for (int i = 0; i < n - 1; i++) {
		graph[u[i]].pb(v[i]);
		graph[v[i]].pb(u[i]);
	}
	
	int root = 0;		

	dfs1(0,-1);
	//for(int i =0; i<n; i++) cout <<i<<": "<< sz[i]<<endl;
	
	name_subtree(root, -1);
	
	return labels;
}

int find_next_station(int s, int t, vector<int> c) {
	
	for(int adj : c){
		if(adj < s) continue;
		//cout << s <<"->"<<t<<": "<<adj<<", "<<sz[adj]<<endl;
		if(adj<= t and t <= adj + sz[adj] -1)
			return adj;
	}
	return c[0];
}


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