Submission #57690

#	Time	Username	Problem	Language	Result	Execution time	Memory
57690		alenam0161	Towns (IOI15_towns)	C++17	0 / 100	27 ms	4668 KiB

towns

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


int hubDistance(int N, int sub) {
  	int f[1107][1107];
  	int d[1107][1107];
  	auto dis=[&](int x,int y){
        if(x==y)return 0;
      if(x>y)swap(x,y);
      if(f[x][y]==false){
          f[x][y]=true;
          d[x][y]=getDistance(x,y);
      }
      return d[x][y]; 
    };
	int x=-1;
	for(int i=1;i<N;++i){
        if(x==-1||dis(0,x)<dis(0,i)){
            x=i;
        }
	}
	int y=-1;
	for(int i=0;i<N;++i){
        if(y==x)continue;
        if(i==x)continue;
        if(y==-1||dis(x,y)<dis(x,i)){
            y=i;
        }
	}
	map<int,int> mp;
	map<int,vector<int>> qan;
	for(int i=0;i<N;++i){
        if(i==x||i==y){
            continue;
        }
        int d1=dis(x,i);
        int d2=dis(y,i);
        int l=dis(x,y);
        int e=d1+d2-l;
        e/=2;
        int v=d2-e;
        mp[v]=max(mp[v],e);
        mp[v]=max(mp[v],d1-e);
        mp[v]=max(mp[v],d2-e);
        qan[v].push_back(i);
	}
	int ans=1e9;
	int hwx=1;
	bool ok=0;
	int hx=N/2;
	int hwl=1;
	int b=0;
	for(auto it=mp.begin();it!=mp.end();++it){
        ans=min(ans,it->second);
        int ds=it->first;
        int oth=qan[ds].size();
        int r=N-hwl-oth;
        if(r>hx||hwl>hx){

        }
        else if(oth>hx){
            b=hx;
            if(qan[ds].size()>hx){
                for(int j=1;b>0;j++,b--){
                    if(j>=qan[ds].size())ok=true;
                    int len=dis(qan[ds][j],qan[ds][0]);
                    len=dis(qan[ds][j],y)-len;
                    len/=2;
                    if(len!=ds){
                        oth--;
                    }
                }
                if(oth>hx)ok=true;
            }
            else{
                ok=true;
            }
        }
	}
	return ans*(ok==false ? 1:-1);
}

Compilation message (stderr)

towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:58:29: warning: conversion to 'int' from 'std::vector<int>::size_type {aka long unsigned int}' may alter its value [-Wconversion]
         int oth=qan[ds].size();
                 ~~~~~~~~~~~~^~
towns.cpp:65:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(qan[ds].size()>hx){
                ~~~~~~~~~~~~~~^~~
towns.cpp:67:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                     if(j>=qan[ds].size())ok=true;
                        ~^~~~~~~~~~~~~~~~
towns.cpp:50:6: warning: unused variable 'hwx' [-Wunused-variable]
  int hwx=1;
      ^~~
towns.cpp:6:28: warning: unused parameter 'sub' [-Wunused-parameter]
 int hubDistance(int N, int sub) {
                            ^~~

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