Submission #1065168

#	Time	Username	Problem	Language	Result	Execution time	Memory
1065168		pawned	Towns (IOI15_towns)	C++17	25 / 100	10 ms	488 KiB

towns

#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")

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

#define fi first
#define se second
#define pb push_back
typedef long long ll;
typedef pair<int, int> ii;
typedef vector<int> vi;

#include "towns.h"

int hubDistance(int N, int sub) {
	int a = -1;
	int maxd = -1;
	for (int i = 0; i < N; i++) {
		int cdist = getDistance(0, i);
		if (cdist > maxd) {
			a = i;
			maxd = cdist;
		}
	}
	int b = -1;
	maxd = -1;
	vi dist1(N, -1);
	for (int i = 0; i < N; i++) {
		dist1[i] = getDistance(a, i);
		if (dist1[i] > maxd) {
			b = i;
			maxd = dist1[i];
		}
	}
	vi dist2(N, -1);
	for (int i = 0; i < N; i++) {
		dist2[i] = getDistance(b, i);
	}
	int dia = dist1[b];
	int ans = 1e9;
	for (int i = 0; i < N; i++) {
		int s = (dia + abs(dist1[i] - dist2[i])) / 2;
		ans = min(ans, s);
	}
	vi cen;
	for (int i = 0; i < N; i++) {
		if ((dia + abs(dist1[i] - dist2[i])) / 2 == ans)
			cen.pb(i);
	}
	for (int x : cen) {
		int cnt = 0;
		for (int i = 0; i < N; i++) {
			if (dist1[i] - dist2[i] == dist1[x] - dist2[x])
				cnt++;
		}
		if (cnt <= N / 2)
			return ans;
	}
	return -ans;
}

Compilation message (stderr)

towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:15:28: warning: unused parameter 'sub' [-Wunused-parameter]
   15 | 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