Submission #1035239

#	Time	Username	Problem	Language	Result	Execution time	Memory
1035239		Gray	Stations (IOI20_stations)	C++17	0 / 100	594 ms	940 KiB

stations

#include "stations.h"
#include <iostream>
#include <vector>

#define ll int
#define ff first
#define ss second
#define ln "\n"
#define pll pair<ll, ll>

using namespace std;


vector<vector<ll>> A;

void dfs(ll u, ll p, vector<ll> &labels){
	ll add=0;
	for (auto v:A[u]){
		if (v==p) continue;
		labels[v]=(labels[u]<<1ll)+add;
		add++;
		dfs(v, u, labels);
	}
}

std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
	A.clear();
	A.resize(n);
	for (ll i=0; i<n-1; i++){
		A[u[i]].push_back(v[i]);
		A[v[i]].push_back(u[i]);
	}
	vector<int> labels(n);
	labels[0]=1;
	dfs(0, 0, labels);
	// for (ll i=0; i<n; i++){
	// 	cout << labels[i] << ln;
	// }
	return labels;
}

int find_next_station(int s, int t, std::vector<int> c) {
	ll n = (int)c.size();
	ll ret=0;
	ll cnts=0, cntt=0;
	for (ll i=0; i<=10; i++){
		if ((1ull<<i)&s){
			cnts=i;
		}
		if ((1ull<<i)&t){
			cntt=i;
		}
	}
	if (cnts>cntt){
		return c[0];
	}else{
		if ((t&(s<<(cntt-cnts)))==s){
			if ((t&(1ll<<(cntt-cnts-1)))){
				return c[c.size()-1];
			}else{
				return c[c.size()-2];
			}
		}else{
			return c[0];
		}
	}
	return ret;
}

Compilation message (stderr)

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:43:5: warning: unused variable 'n' [-Wunused-variable]
   43 |  ll n = (int)c.size();
      |     ^

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