# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
1025375 |
2024-07-17T01:01:34 Z |
vjudge1 |
Towns (IOI15_towns) |
C++17 |
|
15 ms |
1116 KB |
#include "towns.h"
#include<bits/stdc++.h>
using namespace std;
int Ddis[201][201];
inline int getD(int a,int b){
if(a==b)return 0;
if(a>b)swap(a,b);
if(Ddis[a][b])
return Ddis[a][b];
return Ddis[a][b]=getDistance(a,b);
}
mt19937 rng(random_device{}());
bool samesub(pair<int,int>a,pair<int,int>b){
auto[i1,d1]=a;
auto[i2,d2]=b;
return getD(i1,i2)<d1+d2;
}
int ok(map<int,vector<pair<int,int>>>mp,int pivot,int sub){
int toleft=0,toright=0,tot=0;
vector<pair<int,int>> Tis;
for(auto [i,x]:mp){tot+=x.size();
if(i<pivot) toleft+=x.size();
else if(i==pivot) Tis=x;
else toright+=x.size();}
if(toleft>tot/2||toright>tot/2)
return 0;
if(Tis.size()<=tot/2)
return 1;
if(!sub) return 0;
vector<pair<int,pair<int,int>>> STUF;
for(auto i:Tis){
int has=0;
for(auto&[q,w]:STUF)
if(samesub(i,w))
has=1,q++;
if(!has)STUF.push_back({1,i});
}
for(auto[s,k]:STUF)
if(s>tot/2)
return 0;
return 1;
}
int hubDistance(int N, int sub) {
memset(Ddis,0,sizeof Ddis);
int pivot=rng()%N;
int farnod=pivot,fardis=0;
for(int i=0;i<N;i++)
if(getD(i,pivot)>fardis)
farnod=i,fardis=getD(i,pivot);
fardis=0;
int X=farnod;
for(int i=0;i<N;i++)
if(getD(i,X)>fardis)
farnod=i,fardis=getD(i,X);
int Y=farnod,K=fardis;
map<int,vector<pair<int,int>>> mp;
mp[0].push_back({X,0}),mp[2*K].push_back({Y,0});
for(int i=0;i<N;i++){
if(i==X||i==Y)continue;
int toX=getD(X,i),toY=getD(Y,i);
int dep=(toX+toY-K)/2;
int distofP=K+toX-toY;
mp[distofP].push_back({i,dep});
}
int candidate2=mp.lower_bound(K)->first,candidate1=(--mp.lower_bound(K))->first;
int R;
if(K-candidate1<candidate2-K){
R=K-candidate1/2;
if(!ok(mp,candidate1,sub&1))
R=-R;
} else if(K-candidate1>candidate2-K){
R=candidate2/2;
if(!ok(mp,candidate2,sub&1))
R=-R;
} else {
R=candidate2/2;
if(!ok(mp,candidate1,sub&1)&&
!ok(mp,candidate2,sub&1))
R=-R;
}
return R;
}
Compilation message
towns.cpp: In function 'int ok(std::map<int, std::vector<std::pair<int, int> > >, int, int)':
towns.cpp:21:36: warning: conversion from 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
21 | for(auto [i,x]:mp){tot+=x.size();
| ^
towns.cpp:22:36: warning: conversion from 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
22 | if(i<pivot) toleft+=x.size();
| ^
towns.cpp:24:30: warning: conversion from 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
24 | else toright+=x.size();}
| ^
towns.cpp:27:18: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
27 | if(Tis.size()<=tot/2)
| ~~~~~~~~~~^~~~~~~
towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:45:20: warning: conversion from 'std::mersenne_twister_engine<long unsigned int, 32, 624, 397, 31, 2567483615, 11, 4294967295, 7, 2636928640, 15, 4022730752, 18, 1812433253>::result_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
45 | int pivot=rng()%N;
| ~~~~~^~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
600 KB |
Output is correct |
2 |
Correct |
8 ms |
1116 KB |
Output is correct |
3 |
Correct |
0 ms |
604 KB |
Output is correct |
4 |
Correct |
10 ms |
1116 KB |
Output is correct |
5 |
Correct |
10 ms |
1116 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
604 KB |
Output is correct |
2 |
Correct |
8 ms |
1116 KB |
Output is correct |
3 |
Correct |
11 ms |
1116 KB |
Output is correct |
4 |
Correct |
10 ms |
1116 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
10 ms |
600 KB |
Output is correct |
2 |
Correct |
15 ms |
1024 KB |
Output is correct |
3 |
Correct |
0 ms |
604 KB |
Output is correct |
4 |
Correct |
10 ms |
1116 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
7 ms |
600 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |