Submission #126106

#	Time	Username	Problem	Language	Result	Execution time	Memory
126106		baluteshih	Towns (IOI15_towns)	C++14	35 / 100	21 ms	452 KiB

towns

#include "towns.h"
#include <bits/stdc++.h>
#define pb push_back
#define ET cout << "\n"
#define ALL(v) v.begin(),v.end()
#define MP make_pair
#define F first
#define S second
#define MEM(i,j) memset(i,j,sizeof i)
#define DB(a,s,e) {for(int i=s;i<e;++i) cout << a[i] << " ";ET;}
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

const int INF=1e9;

int hubDistance(int N, int sub)
{
	vector<int> dis(N,0),a(N,0),b(N,0);
	int x,y,R=INF,RR;
	for(int i=1;i<N;++i)
		dis[i]=getDistance(0,i);
	x=max_element(ALL(dis))-dis.begin();
	for(int i=0;i<N;++i)
		if(i!=x)
			a[i]=getDistance(x,i);
	y=max_element(ALL(a))-a.begin();
	for(int i=0;i<N;++i)
		if(i!=y)
			b[i]=getDistance(y,i);
	for(int i=0;i<N;++i)
		R=min(R,abs(a[i]-b[i]));
	RR=(a[y]+R)/2;
	if(sub==1||sub==2||sub==4)
	{
		int cnt[3]={};
		for(int i=0;i<N;++i)
			if(abs(a[i]-b[i])==R) ++cnt[0];
			else if(a[i]<b[i]) ++cnt[1];
			else ++cnt[2];
		if(cnt[0]<=N/2&&cnt[1]<=N/2&&cnt[2]<=N/2) return RR;
		return -RR;
	}
	else
	{
		vector<int> chk[2];
		int cnt[2]={};
		for(int i=0;i<N;++i)
			if(abs(a[i]-b[i])==R)
				if(a[i]<b[i]) chk[0].pb(i);
				else chk[1].pb(i);
			else if(a[i]<b[i]) ++cnt[0];
			else ++cnt[1];
		if(chk[0].empty())
			chk[0].swap(chk[1]),swap(cnt[0],cnt[1]);
		if(chk[1].empty())
			if(cnt[0]>N/2&&cnt[1]>N/2) return -RR;
			else;
		else if(cnt[0]+chk[0].size()>N/2||cnt[1]+chk[1].size()>N/2) 
			return -RR;
		while(chk[0].size())
		{
			int t=0;
			vector<int> nxt;
			for(int i:chk[0])
				if(getDistance(i,chk[0][0])<max(a[chk[0][0]],b[chk[0][0]])-RR+max(a[i],b[i])-RR)
					++t;
				else
					nxt.pb(i);
			if(t>N/2) return -RR;
			nxt.swap(chk[0]);
		}
		while(chk[1].size())
		{
			int t=0;
			vector<int> nxt;
			for(int i:chk[1])
				if(getDistance(i,chk[1][0])<max(a[chk[1][0]],b[chk[1][0]])-RR+max(a[i],b[i])-RR)
					++t;
				else
					nxt.pb(i);
			if(t>N/2) return -RR;
			nxt.swap(chk[1]);
		}
		return RR;
	}
}

Compilation message (stderr)

towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:24:25: warning: conversion to 'int' from '__gnu_cxx::__normal_iterator<int*, std::vector<int> >::difference_type {aka long int}' may alter its value [-Wconversion]
  x=max_element(ALL(dis))-dis.begin();
    ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
towns.cpp:28:23: warning: conversion to 'int' from '__gnu_cxx::__normal_iterator<int*, std::vector<int> >::difference_type {aka long int}' may alter its value [-Wconversion]
  y=max_element(ALL(a))-a.begin();
    ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~
towns.cpp:59:8: warning: suggest braces around empty body in an 'else' statement [-Wempty-body]
    else;
        ^
towns.cpp:60:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   else if(cnt[0]+chk[0].size()>N/2||cnt[1]+chk[1].size()>N/2) 
           ~~~~~~~~~~~~~~~~~~~~^~~~
towns.cpp:60:57: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   else if(cnt[0]+chk[0].size()>N/2||cnt[1]+chk[1].size()>N/2) 
                                     ~~~~~~~~~~~~~~~~~~~~^~~~

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