Submission #708834

#	Time	Username	Problem	Language	Result	Execution time	Memory
708834		LittleCube	Towns (IOI15_towns)	C++14	25 / 100	14 ms	880 KiB

towns

#include "towns.h"
#include <bits/stdc++.h>
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define F first
#define S second
using namespace std;

int hubDistance(int N, int sub)
{
	vector<int> dis0(N, 0), disU(N, 0), disD(N, 0);
	map<pii, int> mp;
	int u = 0, v = 0, mx = 0, uv, u0, v0, change, R = 1e9;
	for (int i = 1; i < N; i++)
	{
		dis0[i] = getDistance(0, i);
		if (dis0[i] > mx)
			u = i, mx = dis0[i];
	}
	for (int i = 0; i < N; i++)
		disU[i] = getDistance(u, i);
	mx = 0;
	for (int i = 0; i < N; i++)
		if (disU[i] > mx)
			v = i, mx = disU[i];
	
	uv = disU[v];
	u0 = dis0[u];
	v0 = dis0[v];
	change = uv - u0;
	for (int i = 0; i < N; i++)
	{
		disD[i] = (i == 0 ? (u0 + v0 - uv) / 2 : (disU[i] + dis0[i] + change - uv) / 2);
		R = min(R, max(disU[i] - disD[i], uv - (disU[i] - disD[i])));
		mp[pii(disU[i] - disD[i], uv - (disU[i] - disD[i]))]++;
	}
	return R;
	// int cnt = 0;
	// pii check = pii(0, 0);
	// for (auto [p, k] : mp)
	// {
	// 	if (p.F == R || p.S == R)
	// 	{
	// 		if (cnt <= N / 2 && k <= N / 2 && (N - cnt - k) <= N / 2)
	// 			return R;
	// 		if (cnt <= N / 2 && (N - cnt - k) <= N / 2)
	// 			check = p;
	// 	}
	// 	cnt += k;
	// }
	// if (check.F != 0 && sub != 2 && sub != 4)
	// {
	// 	vector<int> v;
	// 	for (int i = 0; i < N; i++)
	// 		if (check == pii(disU[i] - disD[i], disV[i] - disD[i]))
	// 			v.emplace_back(i);
	// 	int cur = 0, health = 0;
	// 	for (auto i : v)
	// 		if (health == 0)
	// 			cur = i, health = 1;
	// 		else
	// 		{
	// 			int d = getDistance(cur, i);
	// 			if (d == disD[cur] + disD[i])
	// 				health--;
	// 			else
	// 				health++;
	// 		}
	// 	health = 0;
	// 	for (auto i : v)
	// 		if(i == cur || getDistance(cur, i) < disD[cur] + disD[i])
	// 			health++;
	// 	if(health <= N / 2)
	// 		return R;
	// }

	// return -R;
}

Compilation message (stderr)

towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:10:28: warning: unused parameter 'sub' [-Wunused-parameter]
   10 | int hubDistance(int N, int sub)
      |                        ~~~~^~~

• Subtask 1: 13 / 13
• Subtask 2: 12 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 10
• Subtask 5: 0 / 13
• Subtask 6: 0 / 39